The thing is, Cyclizar is not banned anymore. Its shed tail that's broken.
After Cyclizar left OU in January (i think), orthworm started terrorizing the tier. Cyclizar has been used more due to its speed, utility with rapid spin and knock off, and regenerator synergizing with Shed Tail, making it only use 1/6 of its HP. Orthworm loses out on all three, however a slow shed tail has been argued to be more effective than a fast shed tail. With slow shed, Orthworm can tank a hit and bring another mon in for free, with sub intact. This is different to fast shed, where Cyclizar would be the first one to switch, causing another mon, usually setup, to switch in, only for its sub to be broken by an attack, effectively canceling out the shed tail.
Ultimately, slow shed tail has been deemed to broken, however the OU council has decided that shed tail is the problem, not Orthworm or Cyclizar. Shed Tail then promptly got banned in April, and Cyclizar was unbanned. Both Cyclizar and Orthworm failed to reach the usage needed for OU and fell to UU during the first tier shift.
In my opnion, I feel like Cyclizar might find a place in RU. Only Barraskewda and Weavile outspeed it, and there are fighting types in the tier to check Weavile (not sure about their viability). Cyclizar's utility may be able to carve it a niche, as it is the only rapid spinner with knock off other than Toedscruel, which is a solid mon but lacks speed and pivot ablity with U-Turn. Meanwhile, Orthworm may find itself in NU or PU. NU has some fire and fighting types, but while Cricorio and Tauros Paldea are decent (i think), the other mons in the tier may not have what it takes to break past 145 defense, potentially boosted by iron defense or coil and could fire off boosted body presses. In PU, there are special fire types like Charizard and Pyroar, but other than those, I don't think anything else can threaten it enough to stop it from setting up.
In conclusion, Cyclizar isn't broken. It's shed tail.