* People will engage more with your post if they have content warnings. They won't boost un-CWed stuff for risk of upsetting other people.
* If you constantly post stuff that heavily falls under 'should be content warned', people will just block you. Again, you'll *lose* engagement for not using them.
*If your reason is that you, personally, don't like clicking content warnings, here - https://mastodon.art/settings/preferences/appearance . Scroll to the bottom.