I feel the same way except I don't think Bitcointalk will ever disappear, at least not before Bitcoin itself fades into obscurity, which is gonna be a long while from now, with any luck.
Satoshi's posts are too important to the internet for this forum to fail, and even though there's been controversy due to the URL change (among other things), this is the best place to view them... in their original context, just as they were 13-14 years ago.
To be honest, I don't think the post quality has dropped as much as @The Sceptical Chymist is mentioning. There are certain boards that have huge megatopics that suffer from inferior quality, and it's basically all about quantity, which is the gambling board and the bounty sections. The first is a result of signature campaign requirements on the board. Even though I also have a 10 post requirement, I refrain from replying to megathreads that have no reason for existing. Some are so badly written that I'm annoyed as well, such as this one: "
Double your money and quite". They can't even spell the word "quit." Why even bother replying to this topic? Yet, it has over 40 pages of replies.