That's planking. It happens to a lot of older pins that have been improperly stored. As long as it doesn't chip it should be fine.

Have you read vid's guide?

https://pinside.com/pinball/forum/topic/vids-guide-to-ultimate-playfield-restoration#post-547752

It explains planking better than I can. Magic Eraser and clearcoat is the best fix.

You can definitely wax it and play it like it is. All of my EMs are that way. If you ever decide to restore the playfield then would be the time to address it.

As far as I was aware, that wasn't planking--just cracks in the topcoat due to age.

Planking usually shows as straight lines of raised paint. Basically, the wood grains swell, and push the paint off the surface of the playfield.

Planking.

Yep. Planking shows lines that follow the woodgrain from wood expansion, usually from environment factors.

The spider web cracking that you see on older games before clearcoat/Diamond Plate are from the lacquer wearing out, and dirt gets into all the little cracks and lines creating the visible wear that you see. Only way to clean that out is with an abrasive (like Magic Eraser), at which point you have removed the lacquer and are starting to get into the paint, so you need a new top surface to protect it, either mylar or clearcoat.

I wanted to call it crazing at first but thought I was thinking of backglasses.

Thanks for the correction.

If you're planning on selling, I wouldn't hit it with Magic Eraser. There's a good chance things will get worse unless you're willing to touch up and clear. Magic Eraser will take down the finish along with the dirt. If you really want to have a go at it, just go easy and don't go nuts with pressure.

Unless you are going to clear coat the playfield, just wax it and leave it alone.