True but in the physical world a landlord has a monopoly over the parcel of land. Valve has a ton of competitors that seemingly get no traction and Steam is beloved.
No landlord owns entire planet. You never need to agree. If you want to open your store (=sell your game) you can always just rent or buy some other place that this landlord doesn't own. Like for example 150 kilometres away from here where you may get 2 visitors per day, sometimes there will even be humans.
Same with Steam. You are absolutely free to sell your game not on Steam. Except that unless you're a super massive giant selling highly anticipated game you might get no sales. But the choice to eat or starve is always up to you.
