Good points from both of you. I cannot speak for others, but I have never ever had to follow the market. I think having to follow a market puts the most important things down in the list, which is not a good thing. In other words,
If you need to put food on the table before you think about making a software that you love and think is unique and solves a problem, then you are not doing your job because you love it but because you have to. That does cause one thing, instead of focusing on things that matter to you, you start having to buy in the industry noise all the time.. You change your stack every two years because somebody else wants it etc, not because it is truly beneficial.
If you stick to what you love, you do not get tired,you learn faster, better and more importantly more in detail. You start to create unique and better software. This can eventually create your "own"market. It is very very hard,but it is way more valuable than what the market can offer you.
Do not forget, when you create your own market, you are the most important part of your work, your business, your way of doing things..etc But that company you are working for can replace you in 2-3 weeks if something happens to you.
Therefore, I know it is very very hard, but do what you love.