Apple was never niche within the industry, they were the forefront of mainstream. Now they've alienated absolutely everyone and their only direction seems to be toward proprietary nickel and diming.
My Apple days go back to the first era of Steve Jobs. I remember when Macs served mainly DTP (desktop publishing) and Education markets and not much else. Back when people literally said "Macs are toys". I used to get weird "Why?" looks when I told people I used a Mac. I don't think any Mac user from that era would say Apple was "at the forefront of mainstream".
When you say "the industry" - I inferred computer manufacturing industry. As in IBM, HP, Dell, Apple, etc. whereas you appear to be talking about the creative industry.