I'm not sure what exactly you mean by "always active desktop sessions" but for any definition I could imagine it is possible to do that while having e2ee. Many e2ee messengers have multi-device support nowadays.
Telegram doesn't need to have e2ee because they've pulled some trick of becoming widely perceived as being privacy friendly despite not actually offering any e2ee in most cases, and offering only some 🤡-protocol in the few cases where they do.
Another reason for them not to implement e2ee is that they're most likely monetizing their users content data as well as the metadata (and in more ways than just charging some types of police for access to it, which is presumably only a small fraction of their revenue).
I'm not sure what exactly you mean by "always active desktop sessions" but for any definition I could imagine it is possible to do that while having e2ee. Many e2ee messengers have multi-device support nowadays.
Telegram doesn't need to have e2ee because they've pulled some trick of becoming widely perceived as being privacy friendly despite not actually offering any e2ee in most cases, and offering only some 🤡-protocol in the few cases where they do.
Another reason for them not to implement e2ee is that they're most likely monetizing their users content data as well as the metadata (and in more ways than just charging some types of police for access to it, which is presumably only a small fraction of their revenue).