@tired_n_bored, most secure if a FOSS is selfhosted, but only if you have and use an own server, for a lot of user because of this, it isn’t an option when they don’t have the needed trust to a third party server.
Anyway, it’s very important, something nobody does, except me, to read the PP and TOS of a product, there are often bad surprises, independent if it’s FOSS or not.