Here is what I did that resolves the issue of "WD40 is not a lub" My problem was RX shifters that did not work at all after a few of years of storage - They were throw-away if I could not get them working, so I considered that WD40 was acceptable.
WD40 - did not work. After 2 days still got no movement, so pulled out the big guns
Aerosol Engine degrease - can be anything that dissolves the dried and ineffective grease, toyed with using brake cleaner (I had a can on the shelf). It does not need to be a lube - the idea here is to get ride of the stuff that does not work anymore.
Cleanup with lot's of hot soapy water. No cleaning residues left inside the shifter. Now working but obviously metal one metal...
Aerosol Grease. This is magic - it has a light carrier that gets it to places you cannot normally get grease - which then evaporates away, but being a grease, is the right stuff for the shifter. It's better than oils and teflon lubes etc, as it's a higher pressure lube than those, and the shifter has very high pressure contact points.
You will get away with WD40 and oils, but this will cause the shifter components to wear out faster (and probably won't be a smooth). The wear issue may or may not be a problem you are concerned with.