No. I'll put content from the most recent update in a spoiler tag, I'll not put content that's from a previous update in a spoiler tag. If people don't want to be spoiled from content that's 2 updates past then they shouldn't be reading the last pages of the thread while they're behind.
Let me put it to you differently.
You find and begin a game you like. This game has already had many updates. So you're late, even though it's not your fault. Halfway through the game, you have a problem.
You're looking for a solution in the thread. In your search results, you'll come across spoilers without the tag.
Or
You ask for a solution in the discussion thread. By checking the answers (which will be inevitably on the last pages), you're being spoiled by someone who hasn't set the tag, even though it only takes 2s.
A player who has just discovered and started the game deserves the same respect as a player who has completed the latest update. I'll get B3 via Patreon before it's available here. I won't spoil the B2 because I'll have already finished B3.