Much of this comment is based in misinformation, spread most often by CCP themselves. But you have touched upon some interesting points.
There is no fundamental reason that ESI could ever be used to identify or decloak vessels. Neither xyz location data nor client navigation (ie steering/controlling) a ship is a feature. This was a feature during XML api with locator agents and injecting precise bookmarks directly into the client and a large part of the reason CCP and Third Party Developers came together to design ESI.
https://esi.evetech.net/ui/#/Location/get_characters_character_id_location
IP Addresses are not personally identifiable information, mine is 206.83.113.37 currently. There is no power to having this information.
Discord Relays have absolutely nothing to do with ESI or the EVE Client, that said you are welcome to use my open source relay app Tactical Supremacy / aa-relays · GitLab, All of my development efforts are focused on levelling the playing field and having these tools available to all users.
Botters do not use ESI, they use memory scraping and client manipulation/injection. Techniques that are harder to indentify as illegitimate when legitimate users are forced to use them, instead of ESI endpoints.
I fundamentally believe that a well maintained ESI is core to protecting player privacy, and part of my struggles have been to increase CCPs transparency and fixing the recurring ESI and SSO security flaws.
If you are ever concerned about the level of access Third Party Applications have, you can see (and revoke) them here https://community.eveonline.com/support/third-party-applications/