I doubt many of us actually wear out inserts, as in slowly "blunt" them. Generally they tend to get damaged on the cutting edge, so "sharpening" them would need to be pretty drastic and most likely ruin the chipbreaker.
If you watch Pierre's Garage on Youtube, you will see that recently he showed how to grind carbide inserts (with the appropriate diamond wheel). But there again, he also reviewed some "very cost effective" inserts that he found to be perfectly serviceable, so in that context, would it be worthwhile messing about trying to "resharpen" them?
Murray