For me it is not so much about personal privacy, as against concentration of power.

Insane money combined with capacity of invisible, precise manipulation of mass information is really hurting democracies. Big tech is already richer than most countries, and their negative influence is more visible than ever. So now we, who believe in democratic principles, have to vote not only with ballots, but also with our choices and our conscious attention. The least we can do is resist this concentration of power on personal level. Ideally - do it together.

I used it for a few years on Oneplus Nord, and a few days ago switched to pixel7 with LineageOS. First impressions are that e/os was much more usable out of the box.

I surely have worse experience with banking: Revolut and SmartID app just refuse to work due to rooted phone (worked well on e/os). Other bank app is somewhat more broken - on e/os it didnt fully load but at least showed notificatioms on each transaction, now doesnt and is useless.
Could be due to newer android version on LineageOS though, I didnt investigate that.

Kagi uses russian Yandex and pretend it is neutral “business as usual”:

https://kagifeedback.org/d/5445-reconsider-yandex-integration-due-to-the-geopolitical-status-quo

I was lucky to find https://purelymail.com/ which fit my budget and needs - primarily supporting multiple domains for my family and personal projects without extra costs.

Just took the opportunity to try Thunderbird again and had to downvote myself :) I guess my previous frustrations were related to initial sluggishness while downloading and non-compacting loads tens of thousands of mails from gmail. It still takes some time, but after downloading and compacting my data, search seems to be very responsive.

I am using eMclient for several years now. I would have loved to use open source, but experience of using Thunderbird was unbearably sluggish and glitchy. Other options for windows were simply lacking. EM is far from perfect too, but still better. I hope to retry Thunderbird in upcoming years to check if things under the hood changed much.