Yes, you are correct that a Florida trust doesn't need to file tax forms with New York State simply because some beneficiaries reside there. Here are some points to support this:
New York State taxes trusts based on the residency of the trust itself, not the beneficiaries. If the trust is run in Florida and meets the rules for a nonresident trust in New York (e.g., all trustees live outside New state trust assets are located outside New York, and there's no income from New York), it wouldn't be taxed by New York State. See Panel 4 Florida Trust Considerations for the NY Practitioner.pdf
