I originally built it for myself to use with one niche database that had no IDE support at all. I then gave it to my team and then others. Years ago I began to sell it and I still have large banks and finance firms that pay to use it with that one database. Adding support for other databases was actually very little effort however I don't want to have to do the much harder work of:
a) Marketing to those users.
b) Competing with excellent paid alternatives.
c) The various hassle of support / payment processing for many smaller firms.
So the large finance firms pay me for the one niche database supported, everyone else gets it free but "unsupported".
If a major bank that pays emails a problem, I may have to log in even from holiday to fix it. I'm not doing that for the free users :)