Acheivements rarely add anything interesting to a game IMO.

if a game is not interesting enough to be replayable, performing a series of box-ticking tasks isn't going to help it. The way Achievements are usually implented, the best thing they may be able to do is encourage you to try something you may have missed when first playing... for example after I had played Horizon Zero Dawn I noticed I had completed all but 4 of them, and one of them was for performing kills jumping from a mount which is a mechanic I must have skipped over or forgotten about when playing. The other 3 were just for "New Game+", "Ultra Hard" & "All acheivements" (what is the point of getting an "achievement" for completing the others if it tells you how many of the others you have completed anyway)

The only game I can think of that has implemented them in a truly interesting way is The Stanley Parable, and that's because it is taking the piss out of the idea of acheivements.

I guess for the most part they are not usually a detriment to the final game, but Nintendo generally has high standards and maybe they think it could encourage lazy development? Ultimately if a developer wanted to they can easily put those "achievements" into the game itself they just wouldn't show on a public profile. (Again something not interesting to me, I don't have any of the current consoles but if they require online accounts first thing I do is find the setting to make it private)

No need to apologize for your English. The only other language I would probably be able to write a few sentences at most in another language like Spanish (obviously the second-most common language in the USA).
Achievements would be nice. Xbox invented what we think of as an achievement system, and then Steam and PlayStation followed suit. Even Apple Arcade has an achievement system.
Achievements take almost no effort to implement or maintain, so those that like them should be able to have them. And those that don't care for them should be allowed to disable notifications.
Switch 2 could very well have an achievements system, but there's also a good chance it won't. I think there's almost no chance Switch will get any at this point. It's over 6 and a half years old, and I don't think Nintendo would patch them in either in the very likely event Switch 2 is backwards compatible.

I'd prefer the game to actually reward me with something useful or meaningful, such as an in-game item (some stronger than normal weapon, armour, stat-improving gear etc.), or some behind the scenes stuff like concept art or dev diaries (if allowed).

I used to try and gun for acheivements long ago but it just became headache inducing as well as time wasting for the sake of some artificial replayability for what I see is a useless badge; one example was something like a boss rush you get an acheivement without taking any damage once. With the amount of retries it took, it became more repetitive work than fun and it simply was not rewarding or worth the time spent on it. And the Firefly pendents in Last of Us, getting all of them does nothing except give you an acheivement; I never liked how collectables are implemented like that, it just feels very cheap and superficial. Maybe offer a slight discount on a digital purchase instead, then I'd be more interested (it won't happen of course).

I turned off achievements on my PS3 and PS4. I don't need them and I have no desire to have them pop up every now and then.

Many Nintendo games have in-game trophies and achievements that function in the exact same manner, by the way.

I'm Brazilian as well and I remember when I started posting in english online, back in 2008/2009, it literally took me hours to post stuff and half of it was me apologizing for my bad english as well, lol, so don't worry about it.

Now, I think I have posted this years ago already, but I find really stupid Nintendo doesn't have a similar system based on stars, such a missed opportunity.

Many Nintendo games have achievements, including Animal Crossing New Horizons. They’re used to unlock Nook Currency for accessing various items and features.
Nintendo does track play data on each game, mostly the hours—although every 5 hours, instead of precise numbers. That’s about the only data I think I’ve found interesting outside of high score boards. The achievements are more or less arbitrary values which users “achieve” and that’s that. Not really data I’d personally use. I guess you could say I’m indifferent on the subject, I don’t dislike the idea, but don’t miss them either.

Not a fan of them, I have them turned off on my PS5/PS3/Xbox 360.
To me, they're just a distracting, annoying gimmick that adds nothing of value.

Brazilian here too. Don't worry, people around here are quite nice, they won't call somebody out because of their english.

Well, I don't care about achievements and trophies. I'm not competitive, and most of my favorite games don't focus on it. I feel like the goal is to collect them all to show your friends how good you are at a game. I'm not into that.

It's a shitty system and I hope Nintendo never does it. Developers HATE them.

Well, that is just your opinion that you made up.  You have ZERO sources for that opinion.