That's just the heuristics of detecting whether a tx is a wasabi2 coinjoin. There's also a isLongDormantInRemixes above that that attempts to identify based on the time between remixes whether the cj is initiated from trezor suite.
There are some deeper heuristics defined here which are about as far as you'd get. But are these weaknesses in the wasabi protocol? Or are they patterns that can be broken by behavior?
isLongDormantInRemixesabove that that attempts to identify based on the time between remixes whether the cj is initiated from trezor suite.