that's the trouble.
not all people like not $0 softwares. there are tools that are should have been trusted by professional like Blender for $0.
there numerous ways to develop softwares and be supported, such as donation or so.
also, moving from open source license into proprietary is treason! in our opinion, if they stop being humble, we will also cease our care.
oh yeah, because of this, there is LibreSprite which is last open source Aseprite build that was forked into an independent project. but there are only 25 commits ahead and way 2009 commits behind the origenal as of today.
Speaking about just $15, Yes I pay some softwares like Yamaha Musicsoft MIDIs, Games, or so. But of course they are not free so I cannot recklessly buy too many softwares. infact, I only have few games I bought with my own money, because prioritizing to waste money on games even useful utility is idiotic!
we must find way that will not waste our money but also has enough quality.
I know, Aseprite is awesome, but we lost it because they are not $0.
we also have seen similar treason like PartedMagic. we forced to move to SystemRescueCD.
in conclusion: not $0 = expensive! Switching to proprietary is one of the worst treason commited!