...we're just gmail users because, however sadly, it's still the best damned mail client on the planet. Nobody's even come close since 2004. Everyone's had plenty of time to write a replacement - nobody has because email is a terrible technology and it's a thankless chore to work on/with.
Gmail's interface hasn't significantly improved since... maybe smart labels, several years ago? I'd argue it's been surpassed, and most of it's features are par for the course today.
A much larger reason people are Gmail users is because it's incredibly hard to move providers if you have an (at)mailprovider.com email address.
I actually pipe my Fastmail through Gmail just for the spam filtering. Sigh.
Kinda wish they released their spam filtering service as a stand-alone service.
Assuming spam filtering is "good enough", which it is, I'd rather not have my mail used for helping other people's mail get filtered better. FastMail solely uses email you confirm as spam to help their spam reporting efforts, and you can even disable that setting. No accidental spam gets mined for any purpose outside your own account's benefit.
I also feel Gmail trusts it's own opinion more than yours, with regards to training behavior. I used to have receipts from some stores always marked as "promotions" or even "spam", no matter how many times I tried to teach Gmail otherwise.
With Fastmail, if I push the spam filtering too aggressively then I get constant false positives. With Gmail, there's no tweaking and I maybe get one or two false positives per year, and never anything very important.
Obviously different people have different kinds of emails/inbox volume/etc, but that's my experience.
I definitely think FastMail's default spam filtering settings are good enough as is, but you're definitely right, different people have different experiences. The email address I currently use is only three years old, give or take, so it likely hasn't ended up on nearly as many spam lists (yet) as the average Gmail-user-since-2006.
If you give me all emails of 2 billion people, I can build you such a good spam filter as well.
Err, no. Scrolling through 10k emails is a UX disaster. There's a reason why Search exists, and it's this use case. If your email is properly categorized, you rarely end up with folders that large anyway.
I've yet to see anyone handle email categorization and filtering anywhere close to as sanely as Gmail, and I seem to try everything about once a year, get pissed that nobody else can figure it out, and go right back to Gmail. It's especially important to someone like me who's on dozens of open source mailing lists and needs to cross-correlate conversations between lists ("[List Y] Hey I need to update X to make Y work again." "Go talk to someone on list X and file a bug on X's tracker..." "[Bugtracker X] Bug for making Y work again" is an incredibly common email workflow in OSS-land).
My biggest pain in email these days is that Gmail hasn't implemented any kind of smart filter for idiots that can't figure out their own email address - (namely, people signing up for email lists and using services thinking they have my email address... I keep getting incredibly absurd why-the-hell-are-you-even-emailing-this email including medical records, police reports, travel documents, confidential legal communications, etc. from people who share my particular first-letter-last-name pair).
I more or less feel Gmail's filtering thinks it's smarter than it is, it doesn't value my opinion much: https://news.ycombinator.com/item?id=16813203
I'd say the Mail.app is better than Gmail because of it's design and UX, but it often freaks out on "large" actions like bulk deletes or moves. Gmail the app only reads what it needs, allows easily selecting many emails (>50 at a time), and filtering. You can obviously search, filter, and do bulk actions in Mail.app too, but I find the versions in Gmail to be way better because they're either faster or more reliable.
Mail.app also doesn't totally understand Gmail's tags and that an email appears in multiple folders. I'm always afraid of moving emails around in Mail.app.
2) Filtering and categories are still unparalleled, a decade on. Nobody's even come close to the power of Gmail's tagging and filtering. (Seriously, if you want to see just how bad the competition is, fire up Outlook Web Access and try to create some, even really basic, filters. You'll commonly end up with multiple copies of emails or broken read-state tracking, broken threading, etc. I'm forced to use OWA at work and it's excruciating to the point where I simply don't use their filters at all and deal with Inbox Hell by searching alone.)
3) Searching. Gmail's search engine doesn't seem to have suffered as badly as Google's main search has over the years, and as so it still remains incredibly powerful for "power users" like myself. By comparison, OWA's searching feels like something a CS student would implement in class to check a box on a requirement list.
And that's why I'm on Gmail.
And then Google bought it.
Now it's gone forever.
the best damned mail client