I ask because I see a lot of these dismissive comments on HN which end with "open source it" - and that doesn't seem like a super constructive piece of advice to a new startup team.
FWIW, at my current company, an analytics company, about five years ago, we made it clear that no matter what data we collected, if you leave the service or we shut down, we will get you all that data to take with you in a very reasonable format.
It's always risky to invest in a new service, but sometimes risks bring great rewards, and I think it's helpful if you're giving input, to try to make it constructive.