Mozilla cares about HTTP security first and foremost, as they are a browser vendor. And TLS with ESNI takes care of that. But it punts the problem at DNS. And D

Mozilla cares about HTTP security first and foremost, as they are a browser vendor. And TLS with ESNI takes care of that. But it punts the problem at DNS. And DoH solves that. And 99% of interesting traffic is over HTTP. For email there's MTA-STS (basically HSTS for SMTP), for everything else... um, what's left actually? (P2P networks, but for that VPN is recommended anyway.) Sure, inference from L3 data is still possible. But there's a big difference between looking at just "tumblr", "wordpress", "blogspot", or knowing that you look at which blogs.