Yeah it’s not the perfect model for sure. Usually you did get updates to fix vulnerabilities and bugs, but any major version release would require a new purchase/license.
But any software that requires connecting to a server anywhere just doesn’t work in this model.
In the end there’s not much of a choice. Either you pay more for apps to compensate for the time spent on them, subscribe to reduce your costs and assure continuous revenue, or ads.
Anything that’s perpetually free, unless it has massive communities willing to maintain it, typically ends up like the tools we see here: abandoned/sold.