Just if you have a company in mind waiting for Freetrade to add it isn’t always the best option. Nothing wrong with investing via HL or similar, you can have as many GIAs as you like after all. (What is it about HL, there’s well established and have good terms, a decent platform for long term investments)
As for why it’s not on Freetrade I expect it’s about prioritisation, only so many hours in the day I suppose they may have a list somewhere they work through.