Encryption is not for the poor.

The way I interpreted it was that it won't even apply to the paid "personal" plans.

Too bad. I cancelled my dropbox sub and moved to TrueNAS Scale + Nextcloud + B2 rclone last year. Dropbox could have me back anytime they want me.

There are significant costs to encryption. Any deduplication is gone, losing a single "chunk" invalidates the entire file with no hope of recovery, and, more importantly, support costs are way higher - "I lost a password" becomes "I lost every file, I'll never recover them".

Dedeuplication is a huge cost at scale.

I'm not sure what you mean. Deduplication by hash is free and exactly how Dropbox works, as I recall.

Deduplication doesn’t work with client side encryption, at least not securely because it at the least exposes that the file already exists.

Yes, we agree.

The non-business plans (Plus/Family) are already not cheap, especially if you only need a fraction of the storage space.