ESR is basically a stripped and reconfigured browser for organizational deployments where the trade-offs and defaults are geared towards organizational efficiency and management issues, not individual security and privacy. It pretty much says so right on the tin. It's a weird thing to use that as a starting point for a supposedly security and privacy-focused browser. That's before they add their own cruft.

Tor Browser is the browser equivalent of adding sparklers around the gas tank of a Ford Pinto and then claiming you've now got a vehicle uniquely suited for demolition derbies and bank robberies.