United gives you free access only if you are a mileageplus member I think?

Regardless, having free high speed internet on a flight will motivate me as a consumer every time.

Joining United MileagePlus is completely free, you just sign up.

About the same work as filling out a hotel wifi login.

Completely free as in you don't have to give them money.

But you need to give personal information which also has value.

More personal information than you provide them to purchase the ticket to use the free starlink?

Probably, because you are now associating your internet browsing with your personal information. (I don't know if they have the sophistication to actually do this, but it is very possible.)

The people concerned with that hypothetical can use a VPN.

At most they could see domains, ip addresses, timestamps, and http-only sites (are there any left?)

But the person sitting next to you can see everything.

Regardless one of the conditions surely is giving them permissions to sell this to starlink as and everyone else. So whether the information is the same is probably irrelevant, how they are using it is.

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