Are you a pc gamer? Because if you are, I don't understand how you can't see Steam as a massive monopoly.
Perhaps you don't because they have done almost all GOOD with their monopoly power. Offline mode, library sharing, massive sales, etc.. but they are quite a monopoly.
If 99% of my library is on Steam, why should I bother buying somewhere else? It's just an inconvenience to me. Ok I can buy off GOG and have no DRM.... how does that really help me? I can already play it on steam with no problems, my friends can play the shared game on steam, I don't have to worry about multiple platforms etc..
Anyway- steam is a massive monopoly and we are lucky they use their powers for good!
Like Walmart or Amazon, the problem is for devs, not customers.
That is why they have been forcing exclusivity. That is the point: they are anticompetitive.