What you described is aliasing, not compartmentalization. To effectively compartmentalize requires a different email, phone, and CC for every service. By only having one alias of each, the ad networks that are sharing information about you with partners have no obstacles tying together your habits when they see the same proton email, etc across several vendors, even if you have a different name on your alternate products. After these have been matched enough times, there enough of a profile on you to effectively know who you are, even if it is just probable instead of proven. You mention proton, which allows several emails on a paid account, and there are several competitors offering a similar service with varying success, so this should be no problem to implement. There are also companies that offer anonymous CCs, although they are slowly not working. Privacy and Ironvest are two that used to work but I'm not sure if they still do. I'd be interested if you know of CC companies that still work most of the time at vendors. Regarding phones, there are several sources for this as well, depending on whether you want long term or just one time use numbers, but these likewise have been failing as security measures increase.