Okay imma go over this. Some of it is correct and some is just blatantly wrong.
Terrible mobility is 100% true. He's a slow dude but that's his design
Slow buttons again, that's his design we've learned to live with that.
Bad jumps is just incorrect. His jump arch is floaty, yes, but J2 is one of the best jump ins in the game and allows him to get a lot off of jumping over stuff at certain ranges. (You end up jumping further away for jump ins as swamp thing because of how huge j2 is, this makes AAing him hard if used correctly)
BF3 not going under most projectiles is just a gigantic lie. It goes under basically all of them. If you're getting tagged, you need to clean up how you use this tool because it does exactly what it's supposed to.
It's super easy to get trait out when F23/B23 xx 4 is safe. And when you actually get the hit, you get tons of ways to set it up.
Swamp Thing having "no particular strength" is a lie. He's got some of the best neutral in the game, very strong mixup game from D2 tick throws, strong staggers in B2, and B22. B223 has a pokeable gap but B22 xx BF3 has no pokeable gap so that's a 50/50. Essentially youre playing heavy neutral, and making them respect F2 range. When they respect that you can do stuff like dash up command grab. Also log at a distance is so strong, absurdly plus, great for Oki and for counter zoning.