That's fine when you run mutt on your local machine, but the whole reason to use mutt is so that you have a dedicated email machine that you can ssh into and use screen to access email from anywhere. And then things like this become 10x harder (I never found a way, although last I tried was 15+ years ago). Attachments, too.
That's certainly a valid reason to use mutt, but this is not at all why I use. I use because I prefer keyboard control, customizability and a simple, clean UI. Also because it's actually the least sucky (IMO) of local email clients.
One of my main reasons for using Mutt is precisely the opposite: with mbsync I have copies of all emails on my laptop, so I can read, search, and compose emails when I don't have an internet connection.
Why would anyone use mutt when you can have 'local' (ie on a machine you ssh into) Maildirs? That's one of the selling points for using mutt. Imap sucks, it's just something we have to put up with for lack of something better, but I've never searched mail as fast as when I could just grep for what I needed.
I use Thunderbird and it's installed on multiple machines where I have it configured to access the same email account via IMAP. I never really had a problem with out of sync mail and searches are done locally on the machine rather than on the server. I don't have it configured to use Maildir, but the files that store messages are in plain text and I could use grep on them if I wanted to.
