FWIW I just traded my 2011 T4R for a 2020 T4R. All the bells and whistles are nice but they are a confusing a hell to try and navigate while you are driving.
The biggest upgrade from my 2011 is memory seats (limited) with cooling. Also the BT streaming seems to be more stable, the 2011 would get confused all the time.
The big tickets (from what I can can tell) between the 19 and 20 is the
TSS - Garbage
LDA - Garbage
Radar Cruise Control - Useful but a weird, you need to trust it - which I don't.
Larger touch screen - Looks nice but the SW is still Garbage.
So in the end if the 18 or 19 will work and you will be happy with it, take the deal.
I also suspect that the 6th gen 4runner will be a hybrid, cause Toyota trucks MPGs suck. JMHO.
You could get the new Bronco too. It's all the rage in the Toyota Forums.