I've tried the alternative for Photoshop and came out unimpressed. It's even worse for Illustrator, and I hate this software. They're not perfect. I don't like the pricing either or their attitude. Still, After Effect, Illustrator, Indesign are very good. I'm not ripped off with the suite at the end...

I have the same issue with Maxon and Zbrush: nothing is close, but it's still the best at what it does.

We have an even worse company around: Autodesk. And they have competition in the CAD, 3D creation world (that they tried to destroy, but Blender changed the game and Houdini is another world)... but not so much around Revit. Architect would destroy them if they could. But no alternative works.

So let's not insult user here: people tries the alternative. They're not good enough. They're worse.