If I pay you to invent something, and you invent it, I expect to get it. I'm not paying you for the privilege of inviting you to my office. I'm paying you for the output of specific thoughts you have.
The cardinal rule is that, if you do not want your invention to belong to your employer, don't work for them.
All of the sour grapes about these arrangements are indictments of working for someone else, and I wholeheartedly agree! If you have the least bit of cojones, make something people want and sell it yourself. But, if you prefer the golden yoke, the owner of the farm gets all the fruits.
I agree with the sentiment of the first sentence, if we simply say the blast radius is the the product(s) level you're working on.
And all the salary too. I really don't see the issue.
"Very cool and healthy that people on this website instinctively imagine themselves as the boss of random commenters on a website."