May I suggest not offering lifetime updates? All software that does this ends up getting around it in the end because they realize they need to get more money from existing customers to actually stay afloat. Normally by releasing the product under a slightly different name or some other sleight of hand. The model like jetbrains does with IntelliJ I think is decent. Or look at smaller software like sublime text or Arq…
Maybe I'm old school, but I won't "buy" (rent?) subscriptions for software. I expect to own it outright, at to receive at least security updates for a reasonable time period.
In theory you could have a single binary that never changes, ever, but it's just unrealistic.
Subscription models are fine, Jetbrains is the fallback if you're going to be super adamant about refusing to fund ongoing development, but software is not like other products. Maybe in the past when it was very simple within a simple ecosystem it was different.
There's something to be said for reducing the pricing to something more sustainable and more explicity upstream donations, but "pay once, have the developer continue to work for me for free if I keep it long enough" isn't realistic.