I thought about using ProtonMail but it occurred to me that just about everybody I email doesn't use a secure email service, so while my email might not have been data mined at my end, it surely is at the recipient's end. Or am I missing something?
Also, from a security perspective, could Safari have been on your browser list (aside from the fact that it's not that great)?
1-The more people move to secure email services, the more you don't have to worry about the other end of things. The more people resist and cling on privacy abusing services the more public privacy breaching will remain the "normality". Someone has to push the ball forward.
2-While your emails can be data mined on the end of the recipient user, for them to have complete history of your messaging they have to collect data from Gmail, Outlook, Yahoo, Yandex, and every other email service/server out there. If you use privacy invading email service, they just have to log in your account and its all there, every email you sent or received or deleted even for a decade or more. Don't make it so easy on the corporate miners..etc.
3-Security is different from privacy, privacy meaning your data is not shared. Security means its locked from malicious/illegal attacks. From a security POV, I don't know I guess its as good as any other browser. From privacy POV, you never know whats built into that Safari code behind the scenes so its always better to use the Open Source Free alternative(FireFox, Brave). Of course, you can trust Apple more than Google since Apple makes money selling services and hardware and Google makes money by selling ads and your data.
Don't be afraid to make the switch, all browsers do the same exact thing its just about adapting and people are reluctant of change, give it a try. If you decided to use FireFox google something called "FireFox hardening" and you can also use Tor browser which lets your browse the internet anonymously.
As an alternative to YouTube I’ve been using
https://invidio.us/ which I learned from Reddit.
You can do that, but you still rely on YouTube, you are just shielding yourself from it.