Corroded copper, Need to be replaced?

I have some copper pipes that look like they are corroded pretty badly. I had a plumber over (on another issue) and he said they will spring a leak if left unattended and should be replaced. Pipes are in the crawl space under the house. The first photo is a side view and the second photo a view from beneath. Both pipes are cold water pipes and they are touching each other. Area is bone dry and there are currently no leaks. What do you think? Replace, just ignore or sand the corrosion off and slide some plastic between the pipes? Comments appreciated.

Thanks.

I would clean it with a scotch-brite pad to better see what the pipe really looks like after the verdigris is removed.

It wouldn't take much time to drain the system, cut that out, and replace it.

I would be more concerned about WHY it happened at that location. But clean the tubing and check its condition. That is often just an exterior coating on the tubing.

In the second picture, at the cross, it looks like the upper pipe was previously repaired. If so, maybe the guy got flux all over the place and didn't clean up? Just a guess, though