As someone who has used PhotoMechanic enthusiastically for years and who admires their customer support, my hope, for what it’s worth, would for be a feature freeze on PM6 other than for it be able to run natively on Apple Silicon. There may be a significant portion of the user base for whom those quite mature features around ingestion, selection, metadata handling and transmission are the extent of their needs of PM. Hopefully that would be available as a Perpetual license as now. As a mature product the cost of support should be low.
Where there is a version (PhotoMechanic Premium?) with a wider range of best-in-class features that might include DAM, the ability to pick the sharpest from a burst of several frames, Face ID (who would provide the database ?), integration with the emerging content authentication systems, and the ability to machine read the numbers / names from a players clothing, then those are evolving technologies and I can certainly understand why, if accompanied by a clear and well-defined time line of development and implementation, then that could be offered on a subscription basis. A big question is what functionality would you lose on terminating a subscription.
Martin