Bionics. In the show, The Expanse there's a scene where a guy who had his arm cut off in a space accident is trying to get his company to not cheap out and to pay for a bionic arm replacement instead of regrowing him a new arm. The bionic arm being greatly more superior than a normal arm.
Lately, robotics and prostheses are becoming so advanced I can see this as happening to where people will eventually want artificial designer parts over their own.
Fusion generator reactors are getting closer and closer with each breakthrough. Countries are routinely putting big money behind these projects, and it's conceivable that we see this within our lifetime.
Experiments were recently successful in freezing a rat kidney, thawing it out after 100 days, and surgically re-implanting it. It worked. This breakthrough could be the thing needed to allow for human hibernation aboard long term spaceflights. (Powered by cold fusion, naturally)
Quantum computing is very interesting, and could be a gateway-breakthrough that leads to all sorts of miraculous inventions. The ability of a super computer to precisely model interactions between molecules and protein folding, reliably allowing for the continued improvement to, literally, every drug we use today.
CRISPR, Genetic screenings, and the ability to regrow autologous transplants from host tissue is fascinating. Having to donate organs may become a thing of the past.
It is the same for pretty much all the narrative hand waves that are used to push the story forward. This is not knocking SF but to temper expectations.
Deep sleep/human hibernation.
FTL travel of any description, including FTL communication.
Actually safe autonomous transport and delivery would be a great next step. But the enterprises are putting their pre-alpha releases into the public and killing people which is souring the public to the notion.
Self Driving Cars - were getting used to the idea because of the half baked stuff that's already here but it's realistic this will make it mainstream in the coming years
"Cure" for cancer - the rapid progress in immunotherapy drugs is making more and more cancers realistically treatable. Cancers.are still terrible conditions but it does feel realistic that we are moving towards a "cure". After that it'll be a focus on preventing and reducing the horrible side effects of treating cancers.
Regrowing organs - this also seems increasingly realistic. We're already routinely regrowing people's immune systems for some conditions (autologus ransplants - where the donor is also the recipient). We're also increasingly growing different types of tissues and organs in lab experoments. It's looking plausible although hard to say when it'll become mainstream.
AI - I'm not convinced this one is on its way. What I mean is true General AI. What is labelled AI now is nowhere near General AI; it's sophisticated and impressive but also limited and deeply flawed. We're in an era of hype to drive up share prices but the actual technology is error strewn and is essentially a remix engine for human generated creativity. I'm not convinced true General AI is on its way because at the moment they don't understand how the current AI systems work. It's unlikely you can proceed from what we have to full general AI stumbling around in the dark or by shear luck. Not impossible, but unlikely. I think the current methods will more likely hit a brick wall in prpgress - they are useful tools but may be an illusion when it comes to full AI.
Big uptick in the amount of human activity in space — tech there already, economy starting to manifest it. Like 10,000 humans in space at any given time, then 100,000, then 1,000,000, and so on
If we can get a slightly lighter solar sail material, that’s the last missing tech piece needed to send probes to Alpha Centauri. We’d need massive laser arrays so tech alone would precede economic manifestation by a while. Human laser-accelerated probes can reach 0.3 c, and arrive at the star in about 15 years. The probe’s design is the size of a thumb drive
AI is obviously making big strides
honestly my thumbs are cramping up, but there’s lots more. drone-v-drone warfare, all semi-autonomous
Growing perfect genetic match organs to implant
mRNA delivered by microplasmids is incredible. There are easily a million life-enhancing distinct uses of it that involve
temporarily building any protein we want in a patient’s cells, endogenously, with controlled expression. That is crazy powerful technology
Fusion power’s like almost there. I think we’re at the “now scale it” phase
Bombarding Earth by hurling containers full of rocks out of railgun launch tubes on the moon
Sex robots
Translating to and from animal languages
Cloning, which has existed for decades now, is somehow totally invisible to media attention. Like, in the time since Dolly the sheep was in the headlines, someone could have theoretically produced an actual army of human clones and have them hidden somewhere
Telepathy via neural implants
That’s some of the sci fi stuff we either have now and just are too harried and exhausted to contemplate, or that we’re just on the verge of creating.
AGI lead government that is written like a constitution and bill of rights. The infinite persistence factor without human needs or motivations is a major improvement over anything that has ever existed.
Clarke's 3001 had a whole post script about all the sci-fi elements that had actually been realised since he wrote 2001 (back in 1968). It's rather an interesting list, but unfortunately my copy of the book is buried deep in a moving box atm. so I'm not going to quote it.
Space colonization , I could see a colony on the moon being feasible in the next 20 years probably more akin to an oil field where it's mainly people extracting minerals and not recreational.
AI is already well underway, so that's probably the most plausible soonest.
A fully reusable rocket in the form of Starship is also well underway and should be successfully orbiting for the first time soon. Just a matter of a year or two before it's doing workhorse cargo launches probably.
The new round of superconductor possibility might pan out, which would be another one. But that's more of a yes/no outcome that hasn't quite been settled yet, rather than something with a "completion bar."