Clients like Thunderbird are great because you have everything stored locally so you can easily search offline. They also support encrypting and decrypting emails in PGP. However, they seem to have the same limitation as protonmail where you can’t search through encrypted emails....
This does not answer the question. OP wants to Thunderbird to decrypt PGP mails. Yes, it makes sense to use an encrypting fs, but we are still missing this thunderbird feature.
Honestly, I can’t think of a good reason. This is just how email has always worked. What Thunderbird stores locally is identical to message on the server. It’s not decrypted because no conversion happens when syncing mail.
I agree, it would make sense to keep plaintext emails locally or on a trusted server for practical reasons.
Why Not Store Encrypted Emails in Plaintext Locally?
Clients like Thunderbird are great because you have everything stored locally so you can easily search offline. They also support encrypting and decrypting emails in PGP. However, they seem to have the same limitation as protonmail where you can’t search through encrypted emails....