They could have easily crammed the Steam Deck full of stuff to make it hard to use for piracy - locking down everything, making it usable only to play games you legitimately own, force you to go through who knows what hoops in order to play games on it. That’s what Nintendo or Apple or most other companies do.
But they didn’t, because they realized they didn’t have to. It’s 100% possible to put pirated games on the Steam Deck - in fact, it’s as easy as it could reasonably be. You copy it over, you wire it up to Steam, if it’s a non-Linux game you set it up with Proton or whatever else you want to use to run it, bam. You can now run it in Steam just as easily as a normal Steam game (usually.) If you want something similar to cloud saves you can even set up SyncThing for that.
But all of that is a lot of work, and after all that you still don’t have automatic updates, and some games won’t run this way for one reason or another even though they’ll run if you own them (usually, I assume, because of Steam Deck specific tweaks or install stuff that are only used when you’re running them on the Deck via the normal method.) Some of this you can work around but it’s even more hoops.
Whereas if you own a game it’s just push a button and play. They made legitimately owning a game more convenient than piracy, and they did it without relying on DRM or anything that restricts or annoys legitimate users at all - even if a game has a DRM-free GOG version, owning it on Steam will still make it easier to play on the Steam Deck.
You said prevent, not eliminate. There’s tens of thousands of ways to prevent piracy. They are not infallible, but they are preventatives.
There is nothing on this earth that will eliminate piracy.
Where would you like to move the goalposts now?
That’s not moving goalposts, you’re just arguing semantics. People generally think of eliminate when they say prevent in this kind of conversation…
If anything if they went “prevention” and not “eliminate” like in your sense…it would be even dumber because it would just make the steamdeck a more restrictive x86-processor computer compared to the systems people were already comparing it to up until it’s release
Imagine how it would’ve gone down if people were saying “Of course you can do that, it’s a PC” if people responded with “Yeah, except it’s 10x harder to do things you could normally do on PC”. They wanted it to be close to how a PC is, it was part of the advertising campaign.
Anytime you’re reduced to arguing semantics, it’s not even an argument worth engaging in. So I’m not going to bother responding further to you.