Comment by Springtime

> I don't need those files to stick around forever as part of the chat history, my primary use case is to show someone something. No one will come back to that file ever again.

I'd suggest uguu.se for this. Hosts up to 134MB per file for 48 hours. No BS web interface and can alternatively use local ShareX screenshotting tool to upload directly to it to grab a link automatically.

Discord will render still the thumbnail for the link and then after the file expires it will just stop rendering in the chat history.

There are a few free, donation-supported temporary file hosts of a similar nature. Discord ime provides just enough free hosting to be broadly convenient, while for larger uploads with 'Nitro boosts' to a Discord group everyone participating gains increased upload limits.