If you used a VPN and logged into an account, via some mobile app (ex. email), isn’t your VPN identity also compromised now? The companies know, “this VPN IP address belongs to this email user?”
Looks like Orbot/VPN really only protects you from your ISP watching your web traffic.
What are some other trustworthy free VPN’s to consider, like you mentioned. You listed Proton VPN, which is very good. I know RiseUp VPN is also there.