And as it was said many times, having useful features, a road map and frequent updates will surely justify the subscription cost for most.
Also an option of perpetual licence after subscription would be good to have. Similar to Capture One model, where you can keep paying the sub for latest updates, or stay with last version you were eligible to use, or get a discount of purchasing one. Say PM7 releases in 2024, and after full year of subscription you are able to keep using PM7 (2024) perpetually, however not the features of next major update of say PM7.1 (2025).