How can I keep my client ID a secret?

[pvlkmrv]

I have an app on extended quota mode, which has been on this mode for years. The track features (https://developer.spotify.com/documentation/web-api/reference/get-several-audio-features) endpoint is now deprecated and doesn't return data for new apps, no doubt because Spotify doesn't want to train and feed everyone's deep learning model with proprietary features they worked hard to create. My app grabs a few of these for plotting purposes, because they're interesting, and thankfully I'm grandfathered in, app still working. But this is an obvious loophole for anyone else wanting access to the features endpoint: My client ID is just there in the source code, available to be stolen and used by anyone who wants to train their model. I don't want to deal with that potential traffic detracting from my app's budget. Is there a way to close this loophole? My best guess is no, and Spotify will still be inundated and eventually completely remove all access, which would be pretty sad.