Monsters of the Multiverse updated the Bugbear, and I think WotC gave us more than they intended. Yes, they get Fey Ancestry now. Neat, and maybe an unexpected change to the race’s lore. Yes, Sneaky is now back to fixed proficiency in Stealth, and also bugbears can squeeze into small places. Neat, but not massively impactful.
But Surprise Attack is really problematic now. Previously it only worked on surprised enemies and only once per combat. It was fun at low levels, but it was hard to use and it stopped being effective as the 2d6 damage stops being significant. The updated bugbear no longer requires enemies to be surprised, just that they haven’t acted yet, so instead of needing to surprise enemies (which is often beyond an individual players’ control) and then roll well on initiative, now you just need to roll well on initiative.
Oh, and Surprise Attack is also no longer limited to once per combat.
Just in case it’s not clear what that means: The Bugbear’s signature trait (no, it’s not Long-Limbed) now turns the Bugbear’s first turn into a terrifying burst of damage. I’ve spelled out some specific combos and builds in the handbook, and honestly the damage output is terrifying. The Bugbear may be among the most powerful races in the game now.