from https://www.linuxuprising.com/2019/07/how-to-completely-disable-tracker.html

Disable

systemctl --user mask tracker-store.service tracker-miner-fs.service \
   tracker-miner-rss.service tracker-extract.service \
   tracker-miner-apps.service tracker-writeback.service
tracker reset --hard

Check with

tracker status
tracker daemon

Enable again

systemctl --user unmask tracker-store.service tracker-miner-fs.service \
   tracker-miner-rss.service tracker-extract.service 
   tracker-miner-apps.service tracker-writeback.service