Shifter, Linkage ot Transmission Issue?

500mi from home yesterday, car would not start again (2nd time in 2 days).
All lights/warnings working in all positions except start. Turn key to start car
and nothing happens. Noticed the shifter seemed "soft" between P and R.
Shifted down to L and back up. When the Shifter read P, the car was still in
R. Pushed a bit harder and it went into P and the car started.

Shifted to D and the car was still in N. Had to drop it to L, then 2, D, N, etc.
and finally managed to get it into D. Managed to get home and was able to
get the car in P after a couple of tries. All I can say is the shifter feels "soft"
as if something is loose or worn.

I would appreciate any insight into what you think the issue might be and
how I can go about a preliminary diagnosis. Shifter in console? Linkage
external to tyranny? Internal to tranny (yuck)?

Contrary to this post, I am pretty handy and do remove and replace items
under the hood like water and PS pumps, etc. have removed dash and
console to install stereo, have replaced speedometer cables and fixed a
broken bushing in a shifter linkage in another car. I do have access to repair
manuals via AlldataDIY.

Sorry this is so long and rambling. Thanks for any insight and helpful advice!