Somewhat. The distinction I would make is not computer crimes vs other crimes, but rather the timeliness of the situation. For an emergency situation, or a case where a wanted individual enters the country anyway, I agree they'd be foolish to let them return home and only then try to have an arrest made. But there's also no reason prosecutors should lie in wait
until you visit the US to even bring charges. They should decide you're being charged, issue a warrant, and try have the arrest made, including asking other countries for cooperation.
But the alleged crime here is years old, and I have don't remember anything (or find anything in a google news search-by-date) to suggest there were charges or an arrest warrant before July 2017. That makes it seem like they didn't think the evidence was strong enough to get British cooperation, and waited to even mention it until they'd have have a chance to act alone.
Either that, or they really had nothing linking Hutchins to Kronos until very recently. If it turns this really was based on new information, and the timing really was coincidental, I'll be a lot more comfortable with how it was handled. But that's sure not what it looks like right now...