I am looking to migrate my personal mail to a free service that has reasonable storage space, supports IMAP, and is headquartered in the EU. So far GMX.com is the only one that fits the bill, but the free tier benefits are a bit too generous. Is there a catch?
I've been there with my main e-mail address for the past 25 years.
The catch is that their webmail page sucks monkey balls, is loaded with ads (including in your inbox), and every time you log in, they try to rope you into a paid "upgrade" using the worst UI tricks and dark patterns known to man.
Their app sucks, too.
But if you use ublock to access the website and Thunderbird to access your mail, there's no issue.
They make their money by exploiting tech-illiterate people who don't know how to set up an external mail client, accidentally click the upgrade button, and are too afraid to refuse paying. So in short, someone's grandma finances your email address.