I think the only problem that view all solves is to avoid clicking next and previous. If clicking all overloads the server when triggered by many people at a time, while not disable the function. I can't imagine what will happen when I click view all in Premier League mega thread of about 6k pages.
If you click on "see all", you will request +20k posts from the server. This will require more from the server. Just a few people doing it at the same time is no big deal. But if there are, in addition to people, hundreds of bots, it could really overload the server and make the forum stop working properly.
you know that button - the clickable new button shows at the end of the thread title that takes you the the latest posts in a thread... can it be moved to the front?
Are you talking about this button?
And your suggestion, to move it to before the topic title.
Well, I don't use it much, so I don't see much difference in its usefulness. But, for those who use it, if this is really useful, it may be something to change.