Users are given a choice. There are mountains of alternatives to adobe products. But they keep paying for the adobe one because it’s the best. And it’s the best because people keep paying their monthly subscriptions to fund it.
They might complain but at the end of the day they are very happy to pay adobe for the best in class tools.
The industry keeps paying because of the sunk costs of legacy files and content, and the fact that Adobe also makes RIPs for imagesetters so the expectation is that it will all be compatible and work together.
And thank god for that.
Users literally hate the Adobe model, but aren't given a choice.
Please remember what the 'F' in FOSS stands for. Hint: it's not about money.