@mhoye Alas I haven't found such a broad liar, but for other info like browser location spoofing there's https://addons.mozilla.org/en-US/firefox/addon/location-guard/
Why of course I'm in London now. Wait, nope, I'm in Moscow. Or Dubai. Or...
Download Location Guard for Firefox. Hide your geographic location from websites. Report a fake location with the addition of random noise in order to protect your privacy. Per site settings with three configurable levels of accuracy or even the possibility to use a fixed location.
@mhoye There are tools that do this AFAIU, not sure of deets. I think LineageOS or F-Droid would be good places to look.
I tend to answer registration-email-required forms with ceo+<random-value>@domain.tld, where domain and TLD match the site requesting the information.
sales+<string> would likely be even better.
Choke those channels.
("Plus-notation" email addresses typically get delivered to the addressee before the "+" symbol, the rest is used by the sender but ignored by the receiving system.)
Sounds like a plan...