Because with Overwatch 2, the changes were so small and meaningless that it could have just been an update to the original game. CS2 is on a whole new engine and has significant upgrades that couldn’t have been implemented in a simple update. Not to mention all the promised features OW2 was supposed to have that they backtracked on. That being said, I don’t exactly agree that they should have outright replaced CS:GO, but it’s not really the same as what Blizzard did. If they had replaced the original OW but had a significant reason to do so like Valve did, people wouldn’t be so upset at them.