Observing that different rights may sometimes be in conflict is not transphobic.

A definition of transphobia is not enough to provide the clarity needed just now.

We also need to explicitly state what isn't transphobic to curtail spurious accusations that have caused much of the rancour & toxicity.

I mean, you may think it's obvious, but here we are.

It isn't transphobic to observe that:
1) sex is real & matters politically
2) rights may sometimes be in conflict
3) no-one is exempt from safeguards

It is transphobic to state that:
1) gender identity is not real or doesn't matter
2) precautionary safeguards imply collective guilt

Also, rights may sometimes come into conflict, but that doesn't mean they are in general expendable, it means we work out how to reconcile them with highly limited exceptions with the narrow set of circumstances in which they are in conflict.

It would be transphobic to infer general expendability from the requirement for particular exceptions.