> companies should be legally forbidden from blocking 3rd party clients While, in cases like this, I agree with you, I think there needs to be nuance to a rule

> companies should be legally forbidden from blocking 3rd party clients While, in cases like this, I agree with you, I think there needs to be nuance to a rule like this. Consider what would happen in the reverse case. A competitor arises to some aspect of Facebook's services—say, an app that does something kinda like Instagram, but not quite—and becomes somewhat popular. Facebook adds support for accessing this competitor's service from their own app—look how convenient! You don't need to download two apps, just our app! They replace the ads from the service maker with their own, thus starving them of revenue...or they just wait until some critical mass of users access the other service through their app, then offer free and easy migration from the other service to their own. Then they start introducing UX problems with the other service—oh, but it's not their fault. It's because of changes to the API or ToS of the other app! In short, if this sort of thing is mandated universally, it simply tips the scales back in favor of the behemoths already ruling the roost, who can afford to build support for a dozen competing apps right into their own, and use the good old Embrace, Extend, Extinguish (or any similar playbook) to make sure the competitors die of asphyxiation.