Some of the worst games on Roblox are the endless array of identical RP games or tycoons that become increasingly pay to win as the months pass. But these have been around for ages and will continue to be a mainstay.
I feel obliged to mention PVE-based games that have poor enemy design are quite the spectacle as well.
Dungeon Quest is a really big offender of this since most of the enemies have rather basic AI. Now, compare the humanoids that walk in a straight line towards you to a
few other examples from games that were either made before or after it. Generally, I just play PVP games since that would (obviously) take advantage of the multiplayer aspect of the platform. That
does, however, remind me of the mess that is Catalog Heaven.
Catalog Heaven used to be one of my favorite games on the platform because of the sheer unpredictability and novelty of gear. There were already hundreds of gear that did batshit insane shit ranging from a glass vial that turns anyone you throw it at into a pile of goo after a few seconds or a sledgehammer that can fling people hundreds of meters on hit. The game would have a meta that shifted a buttload and, as gears are no longer updated, hasn't changed in a year.
In its current state, the avatar customization is actually worse than Robloxian Highschool of all things since it hasn't updated in a while either. More importantly, though, the sheer unpredictability of gear and Seranok not bothering to fix anything has lead to some crazyass shit happening within the confines of CH's community. Namely,
bots that automatically crash servers, which has lead to some very surreal screencaps of CH at double digit playercounts for like 15+ minutes at a time (like the one below).
Most gears are broken and the gamepass' bonuses have not been updated in quite a while. Where it stands, the items in the banned VIP category ($50 btw) are worse off than most of the items that you can get for free, since they were updated based on the meta at the time. The balance back then was vastly different than what it is now; compare
one-hit kill melees to
weapons that automatically negate flight within 300 studs, deploy reflector shields that automatically heal you, and create black holes that stop all projectiles and guarantee players instantly die within 75 studs of you. Now, I might need to remind you that you must pay $50 for the one-hit kill knife and 40 other weapons like it, most of them being broken and unusable.
The year is 20xx and everyone uses bugged gear items to infinitely accelerate upwards at 200 studs/s^2, instakill anyone within 125 studs of themselves and... that's about it.
Sometimes they don't use the instakill death explosion laser and opt to run into eachother with instant freeze AoE weapons. I think it's kinda boring, I don't know.
Currently I just play Catalog Gear Place, which manually updates its gears or revamps existing ones. Same thing as old CH with the gear updates that used to happen once in a while, except that the geardevs that were laid off their job have some of their unreleased stuff get put into the game.