Really depends on the company. For example American ISPs definitely do that, but then again they aren’t really privacy oriented anyway. Look for an email company that is more privacy focused. Companies like that aren’t really playing the same game as Amazon, Microsoft and other.
“If you aren’t paying for the product then you are the product” doesn’t apply anymore.
Nowadays, even if you do pay for the product, you are still the product, as companies see more money on the table and will go for it.
Really depends on the company. For example American ISPs definitely do that, but then again they aren’t really privacy oriented anyway. Look for an email company that is more privacy focused. Companies like that aren’t really playing the same game as Amazon, Microsoft and other.
True, there are exceptions, and they should be sought out and supported, just not something that can be relied on anymore