Very glib, but not helpful nor accurate. Reliability of a web service? Speed faster than local network or local VPN tunnel? Convenience appears to be the top and bottom of it from other replies.
> assumption that they "are gathering data [...] and selling it" is beyond baseless
Not at all. US freedom of information goes far beyond everyone else's and leaves the expectation that personal data is collected, shared, sold, misused and abused, and that's been the case since long before the web. Personal data that most places consider private and inappropriate to share, and often have laws for, is frequently easily available in the US.
The web just brought it further into the gutter.
Europe has had freedom of information with constraints on personal data. Data protection has been around since the mid 90s, and prior to that there were other restrictions on certain types of data collection. The discrepancy between the two approaches has been there for probably seventy years, perhaps more, and it's widening not narrowing.
Those national norms set starting point of expectations, and what each nation tends to take as axiomatic. For a typical European, for the reasons mentioned, US privacy provision and expectation starts negative. Certain industries and categories get very antsy about data going, even briefly, to the US as a consequence of that. If it's any consolation I start with the presumption every company is untrustworthy.
that is they deserve none. No company gets any trust from me until they prove that they deserve it.
In other words in public my opinion on them is "neutral" until I have some information/data/signs to form/change my opinion, but internally I assume they are doing[0] something evil until proven otherwise.
[0] or at least assume they are capable of doing something evil and there is a non-zero chance that they will engage in evil-doing. (but again, not accusing them publicly until there are reasons to do so; I'm just describing internal thought-process)
The founders appear to live in the US so a US company is a lot more convenient for them, and Delaware has some very nice benefits for companies that AFAIK don't have any privacy drawbacks. Your assumption that they "are gathering data [...] and selling it" is beyond baseless.
EU users are protected by the GDPR anyways and despite what ProtonMail etc. would like you to believe, founding your company in Switzerland or whatever does not make you magically trustworthy.
From where I see it, they deserve no more and no less initial trust than any other company.