>> the fact that a service is critically dependent on a single server or maintainer as a design failure. Software should allow users to be more self-sufficient, not less.
Software allows users to be as self-sufficient or not, depending on their skills and resources. There is room for a whole spectrum of users, and obviously as developers we fall on that spectrum as well.
Self suffiency, in any area, is expensive in time, and money. I can grow my own food by buying the land and devoting all day to farming. I'm self sufficient, but I don't have time for anything else.
Equally I can choose to spend time running my own servers. I can buy hardware, learn many things, make mistakes, but be self sufficient.
However all that time spent is time I'm not focusing on my business. If my cousin runs a school, they want a "system that just works". They aren't interested in being self-sufficient. They don't have the time, or money, to (safely) host their own software. They are too busy adding value to their business elsewhere.
(most) OSS to some extent solves a problem that only very few people have. It caters to those who are time rich but cash poor. Most people though are time poor, and can easily find cash to make problems go away.
Adobe wins over Gimp because it does more, faster, thus saving the user time. Its a lot easier to find money than time, so paying the subscription is trivial. If it saves an hour a month, you're ahead even at minimum wage levels.
Of course there are those who value self-sufficiency, who seek out solutions that reduce, or remove, the supply chain. These folk exist in every part of society, and it is a perfectly good approach.
But it is worth understanding that this is a tiny subset of people. Most buy their food in a shop. Most are just using their computer to perform tasks. They have no more desire to write their own code, or host their own server, than they do to grow their own food.