Oh my.
To start off, you don't get -anything- tangible out of achievements anyway, actually.
Neither are they a part of "game design", as you can put literally anything in there and smack it together in a list.
Here's a little something something:
Anyone familiar with XCOM will know about heavy RNG and having to reach achievements despite of it :>
And you'll have to rely on many more actions that are much less probable than 90%, or even 80%. Your eyes sparkle everytime you reach these numbers! Gear Grind's my best friend.
For reference, the globally least reached achievements from XCOM2 (in % of players). and you can still savestate-"cheat" your way through if not doing Ironman mode (in which the game saves automatically after every little step, and there's only one file for your campaign that therefore gets overwritten - which basically means "do everything right on your first try or restart your whole campaign".)
For XCOM 1 (Enemy Unknown/Enemy Within), I'm among the 1,7% of players beating the game on the at least 2nd highest difficulty with said Ironman mode enabled.
I'm very well aware of the difficulty, and that you in fact do have to know your way around the game very well before going for some of those.
And that, even if you are objectively okay or even good at the game, it will (try to) mess with you in 9,9 out of 10 attempts.
You don't become a legend just by being good - everything else has to align as well.
If it's not worth your time, don't do it - it's really easy just like that. It only means as much as you want it to mean.