One can legally use Community Edition until income hits some limit. Paid edition can be bought and just used without updates.
> use .NET, which is $0
But tracing garbage collection needs 5x more available RAM than used RAM. Native conservative applications introduce memory fragmentation, estimated as 2:1 available:used. That gives 2.5x smaller memory footprint of native apps, and RAM prices matter lately.
That limit is $5000 revenue per year. And this is not scoped down to "$5000 revenue from Delphi projects." It's basically student-only.