Apple mail.app with gmail account performance vs. Thunderbird

[pgolik]

I was a happy user of the system Mail.app since OSX Tiger days, but recently my main work email was moved from self-hosted to gmail, and it became painful to use. I don't have a huge inbox, yet it's slow and takes a long time to sync any changes. For example - I delete a message, but it stays visible until I click on another mail folder and then back on inbox, stays marked as unread even though I opened it, etc. I tried all the solutions I found on the net (like disabling IMAP labels), but it's still painful to use.
I don't like the web interface, so I tried Thunderbird (which I remember from my days of running Linux as the main OS, years ago), and it has none of these problems. The interface is nowhere near as elegant as the system app, and I miss some of the useful OS integration features (like automatic recognition of dates in message body to create calendar events), but it's fast and does its job. And both use the same IMAP protocol to talk to gmail.
Now the question: I'm on an old 2015 15" MBP running the latest supported OS - Monterey. If I upgraded to a modern Mx Mac running the latest OS, would the Mail.app become usable with gmail (that could push me to upgrading sooner than later), or would the issues persist? I'm not seing CPU spikes when I use mail, but maybe newer OS versions solved these problems.

 

[kevcube]

I have used mail.app with gmail accounts and haven't had many issues, on an account from like 2008 or possibly earlier (gmail closed beta) so lots of emails

I now prefer Mimestream because it's using Gmail API and not IMAP. I don't really see a reason why thunderbird would perform any differently seeing as it's still an IMAP client.

 

[pgolik]

I know about Mimestream, but I avoid subscription software whenever I can. Also, both mail.app and TB work with my iCloud account, so I can have work and private stuff in the same app. Isn’t Mimestream gmail-only? I’ve seen reports of performance problems with gmail on mail.app, so I’m not the only one. And while it’s IMAP on both, the difference in performance is perceptible. That’s exactly why I’m asking.

 

[kevcube]

I know about Mimestream, but I avoid subscription software whenever I can. Also, both mail.app and TB work with my iCloud account, so I can have work and private stuff in the same app. Isn’t Mimestream gmail-only? I’ve seen reports of performance problems with gmail on mail.app, so I’m not the only one. And while it’s IMAP on both, the difference in performance is perceptible. That’s exactly why I’m asking.

yeah I get it, just sharing my experience. Yes Mimestream is gmail only. I also like having all my inboxes in one app.

I have no performance issues on m1 or greater Macs using gmail inside mail.app, before Mimestream I had my personal and work gmails in mail.app.