Email aliases via proton or tuta paid - using custom domain from cloudflare, following bazzell ebook

I subscribed to Tuta for this and regretted it, it’s janky to use in general and the custom domains are hard to administer eg new emails received by catchall do not automatically generate an alias making it easy to reply from the wrong address. I’m moving away from Tuta and don’t recommend it for use with custom domain aliasing.