What's the line? If 2 brothers sign a contract, can't they decide their father will be the judge if disputes arise?

If there's a sports match, shouldn't the sports arbiter be able to decide whether some team scored a goal or not?

These are all valid civil contracts. It only affects the civil claims, never criminal, and the venue for disputing the arbitration clause (if you believe arbitration wasn't legal to begin with) are the public courts anyways, who will delegate or not to the private court.

Almost all countries recognize it and it has a quite defensible theory.

It sure is contextual. And nobody would disagree with your examples. The difference here seems to be more of a power imbalance than any objection to terms. In particular, terms of service are often very dense documents. Many people are only presented these documents at the moment they sign up for a service. And people are not usually careful in these situations. I bet most of the Uber signups were outside of bars or venues where someone really needed to get home. So there’s some duress there. So it’s probably not that cut and dried. It’s more analogous to presenting a contract to harvest your wheat field the day before a big rain. If you’re the only guy with a combine for miles then that puts you in a position of relative power. And historically the US hasn’t permitted people to exploit their positions to the maximum extent, usually when it would be immoral by the standards of society. I think this exists in a gray area. It’s not that easy.

I think my gripe is less that it exists and more so that it's not a negotiated agreement. I think it should only be allowed if the contract was negotiated between two parties with full authority to offer any terms in the negotiation. If it's a standardized, take it or leave it, contract where one party has no opportunity to offer alternative terms that get proper and full consideration by the other party, it shouldn't be allowed. In most of the examples you give, they are contracts that have been clearly negotiated between parties, not click-wrapped take it or leave it, my way or the highway, terms.

I think such terms should require signatures and initials. Holding people to terms they are unaware of is not fair.

i think the keyword is "forced". there's very little now that the consumer can do because it seems everything requires arbitration now and people still have to operate in society.

> What's the line?

The line that minimum should be against using this as a tool against consumers. To the extent it should exist at all, which is arguable, it must be between parties that are either equal in standing or have genuine commercial disputes between duly organized business entities.