Look, Valve people speak a very specific way. It takes a while to wrap your head around what they mean.
The quote you're giving me is Valve-speak for "we were cool with your double-dipping DRM back when it was free for us but we now would prefer you don't add it to your game because it makes it harder for us to sell your games on Steam Deck where we control the whole platform".
And yes, those things do apply to Steam. You absolutely don't own your Steam games. Those go away with your account, unless you're actively extracting and repackaging those files for backup. This is itself a breach of Steam's EULA and not a service they provide. It is absolutely a piracy mitigation tool and, while there is a "Offline Mode" you are not allowed or able to install or play your games without online verification as a general rule.
The notion that multiple people here are questioning the fact that Steam's DRM is, in fact, DRM because it's crackable is kind of shocking. It's a testament to their PR, for sure, but also to their ability to do long term moves due to being a private company. It didn't take a genius to understand that the real piracy dampener for PC gaming was availability, price and convenience rather than technically profiicent DRM, but it did take a competent CEO with no shareholders in his way to deploy that strategy.
But that doesn't mean it's not DRM or games-as-a-service. It absolutely is. Valve invented or perfected DRM, online distribution, battlepasses, monetized UGC and, technically NFTs. The branding exercise required to do that and still be perceived as a fan-favorite, user-first company should get a TON more credit than it does in marketing schools worldwide.