Gmail is an email service. Like the fediverse, email is federated.
By changing your email provider, do you really lose anything? You can still contact your friends, contacts and even various customer suports. You also can recieve emails from popular social media apps. If you degoogle from atleast one Google app, maybe Gmail could be the easiest and least life changing one.
While, Youtube could easilly be one of the most difficult to degoogle from. Not like literally but emotionally. Like deep down you know you can find mostly all you might need on something like Peertube but not all the entertainment media like on Youtube. You will also become a social outcast if peertube is the only app you use. You might not understand channels people mention in day to day talk from youtube or references.
If you use exclusively fediverse apps and sites, Chrome could be almost just as easy to replace as gmail, longterm. However If you use Youtube it won’t surprise me that Youtube downgrades your performance and user experience in what ever means neccesary on competing browsers.
I mean- I dont have a domain, been using proton mail and mail.com for the pass 6 years atleast with no noticable issues on multiple popular sites. Maybe you can explain that further maybe i’m not quiet understanding.
I know that ad free apps exist for Youtube however they probally won’t last long term. Ad blockers right now are the main target of google to rid of. Peertube being its own thing from Youtube and also federated will last longer then most sites trying to compete with Youtube as there are multiple hosts for different smaller sections of the service.
It’s just that having your own domain means your email address doesn’t have to change when you move providers, is all.