That is completely wrong -- there are a couple distros out there that work "out of the box" without the need of a custom kernel. Not just for the rpi, but for many other "obscure" pcs, including a thermostat.
I'm definitely not a "potato expert", but what I use (on my orange pi zero 3 w/ 1 GiB of ram, at least) is simply:
zram size= 100% of available ram, zstd, priority set at 100%. Because apparently if theres more zram swap than available ram, it'll lead into memory leaks and/or slowdowns.
I will be using this computer mainly to write documents, make the occasional presentations, browse the web, and watch videos and movies. So no photo- or video editing nor gaming at all.
Then go for a Raspberry pi 3. (No, not rpi 4 or the rpi 5 one). It's cheap, with a power draw low enough to leave it running 24/7 (it will not increase your energy bills by the slightest). Downside is that you'll have to learn some Linux "tricks" that will (definitely) "grind your gears", but eh.... it'll be a fun ride if you are willing to lose some sanity for the sake of enjoying a "It's like nothing is happening to my power bills at all!" power of the convenience it'll bring to your life and your lifestyle as well.
Step 1: "Unlearn" everything you learnt about technology and pcs as a whole and embrace Linux with a open mind.
Step 2: Kill the bad habit (that only Windows gives you) of expect everything to "just werk" and to "solve" all your problems with left clicks. Yes, that is a bad, terrible habit and should not be accepted/be a daily habit for you and no sane user out there.
Step 3: Nah, you'll lose everything -- just YOLO it.
Relying on easy, simple stuff does not (always) mean a good thing let alone being good for you and your mental health. Even less so allowing proprietary, capitalism-driven developers to do whatever they want with your PC (which makes me wonder what you are even doing in this community in first place if you just "don't care"), but hey... you do you.
To use Linux properly, you've got to "unlearn" everything you know about computers and go back from the ground-up. And breaking yourself free from bad habits (that only Windows gives you) such as relying on installers to do the job for you -- i.e "double-clicking your cares away". Which can be a fun experience when compiling (The "turbo nerd way" to install things on linux) becomes "second nature", giving you the ability to taste "true freedom" of making (pretty much) anything work the way as you may seem fit.
...
No, really. You'll have a heck of a nerdgasm when you compile something that is not "normally supported" on an obscure pc/distro. You will feel like a demigod.
t. That is how I felt the first time I compiled a half-life openBSD port... on Linux. I did it "by following my gut" and everything "werked".
For the sake of "saving" your post (even as someone who has no idea how nextcloud works)... I made a quick search regarding nextcloud and the nextcloud docs says it needs a minimum of 128MiB ram per process while they recommend 512MiB which doesn't seem that much of a resource beast at all...? It COULD work, but not as good as your typical nextcloud setup with over 10 processes or something of the sort. Probably a headless/bare metal setup with dietpi, I guess?
Then again, as I said previously... this is a totally ignorant take on saving your post, but eh... who on earth would want to run nextcloud with less than 10 processes anyways? So I'm gonna go with "Yeah it does, but you'll (eventually) want to switch to a better sbc later on."
"What, you don't like retro yet proper gaming on a 1W device?"
-- Me, if I were that lone guy holding a controller