If it weren't so expensive... I was looking at Factorial and Cyberpunk 2077 for months now, but the price is so much higher than the games I normally play.
I have read Factorio's reasoning for the price, but after playing the demo, I don't see how they are in a different position compared to e.g. Terraria or Don't Starve.
My suggestion? Pirate it. Play the full game and see if it's worth your 30 bucks. If it is (and I believe it will be), then buy it on your platform of choice. If not, nothing lost.
Not that your suggestion is necessarily bad in general, but I don't really think it's necessary when it comes to Factorio. I think it should be clear from playing the demo whether 100+ more hours of that seems worth the asking price for someone. It's probably the most representative demo I've ever played; the full game is just the demo but more. There are no surprises down the line. There are no random pivots to other genres, or the game trying to stick its fingers in too many pies. There's no narrative to screw up. There's no "oh, they clearly just spent all their time polishing the first hour of the game and the rest of it is a technical mess". It's the same gameplay loop from the demo for another 50 hours until you "win".
... and then another 50 hours after that when you decide to optimise things. And then another 100 hours when you decide to make a train-themed base. And then another 700 hours when you discover some of the mods that exist...
This. I've run a bunch of lan parties where we just copied factorio around all the computers. The developers don't really do any DRM. Intentionally. The only restriction for a pirated copy, really just a copied copy, is that you can't play on servers that do username authentication. But for self-hosted servers you can disable that. Like for a lan.
And for all the people who came to the lan and played, nearly 100% of them bought the game. Because they love the game.
So if this is the kind of game you love, and you genuinely can't afford it, pirate it, I think the whole community is behind you. And if you can afford it please buy it
I was in your camp for a while and just kept it on my watchlist for forever. Eventually I figured I would probably sink 100+ hours into the game, so the cost per hour of entertainment was quite low. After getting it and playing for more than 100 hours, I can say I'm happy with the purchase and it's worth it.
Neither Terraria nor Don’t Starve are in the automation genre, though! I found Factorio way more enjoyable than those two. Worth what I paid for it many times over. 
Factorio is way different from terraria and don't starve. They're not even the same genere.
Also if you think it's expensive, (not flaming, genuinely asking) is your computer good enough to run cyberpunk at a reasonable graphic settings and fps? Because that games requires alot
Pretentiousness? Or developers charging a fair price for over a decade of development work, the quality of which makes Bethesda and Ubisoft seethe with rage?
I bought Factorio a couple years ago and played for about 4 hours. I thought it was pretty fun but I didn't really get hooked or anything so it sat in my Steam library for a while.
Early last summer I gave it another go and something finally clicked. I probably spent a whole month doing nothing but play Factorio when I wasn't eating sleeping or working. My wife was concerned. It was by far my most played game last year and it's now probably one of my favorite games ever.
If you're into programming or dev ops it definitely aligns with that mindset once you get deep enough in the game you start seeing the patterns and trying to optimize your factory design. But that sort of game isn't for everyone.