Avoid download 100.000 mails from gmail when using Apple Mail

Apple's mail on 10.11 and older will download all the mail that the server tells it about. The macOS 10.12 mail has a setting to optimize mail storage that might store header information for all mails, but not download the body and attachments of older emails.

You can opt in to that from the Apple menu - about this Mac - storage - manage, but it seems to only be offered when you have significant storage burden from Mail and/or specific mail server configurations.

Since that's how the mail client was designed and codes, you will need to go to gmail's web interface and hide some of the folders from IMAP access to prevent mail from ever seeing the messages. Exchange has a setting to determine a time range of mail to sync, but google and IMAP do not have that feature.

Gmail -> Settings -> Labels

Most people I know that use mail like you describe (keep all of it all the time) choose to not show All Mail in IMAP and then just clean their inbox when the volume becomes unwieldy.

Maybe this is a new setting but GMail has a setting under IMAP that you can limit the number of messages per folder - starting at 1000.

GMail >> Settings >> IMAP Settings >> Folder Size Limits