Trust is not binary, I can trust dropbox with certain files but not want them to have complete root/kernel access to my computer.

exactly, thank you SahAssar.

speedgoose speaking for myself I place files in unencrypted folders in dropobx that aren't sensitive in nature, for files that are I place in an encrypted *.sparseimage so to your point it is possible for me to trust the encryption method I use to host my files within their platform but not trust them to have access to my laptops kernal.