The mounts are very easy to glitch out. They can fall inside the ground or rocks. Sometimes the game doesn't register your mount, so it says you can pull another one out, but doing that will delete the one you pulled out. A lot of the time, telling the buggy to stay doesn't work. For instance, I tell my buggy to stay back so I can chop grass, but my buggy walks after me and interrupts my activity. This is like being blocked in a room by a follower who won't move in other video games (Serana).
The building in Grounded 2 is too restricting. For some blueprints, you can only place them from a certain angle (i.e. hatchery) and even after they are placed, you can't build it unless you are looking at that angle. Not being able to clip blueprints into the ground is a serious issue for builders, myself included. When a tiny dirt clump gets in the way of your base expansion and you can't build anything there, it restricts the player to building floating bases or finding flat land. Also, there should be a radius where resources AND BUGS (PLEASE!) do not respawn around blueprints and structures. Being able to block certain bug spawns by building around them would give players a lot more freedom for bases.
Multi-player latency and rubber banding is a common problem, especially when multiple buggies are out at once.
Durability on Whoa mode feels way too low. If I die three times, all of my early game gear is broken. This can make the game feel like a death run loop.