In my humble opinion, any mega fan would have seen how fractured the group had become by ‘69-‘70 and the fact they actually wanted to move on to individual lives with their significant others (John certainly made that clear by having Yoko by his side 24/7 - or, he did to irritate the others to the point of wanting to leave the band - either way, both were rather “kiss off” gestures).
Further, John and George had both become bitter over Paul’s efforts to keep the train rolling among other reasons. They not only wanted a break from one another - they needed a break from one another.
My preference is that they collaborated on one another’s solo works - which they did - and I would also liked to have seen them perform together on special occasions such as a benefit concert now and then.
Although, I think John sums it up best in this clip (one of my favorite moments):
https://youtu.be/Ds82Id_GMe8
"Significant others" ? You mean their wives? Paul showed you could be married and still do tours etc. George was sleeping with Ringo's wife and both would subsequently divorce. John had been with Yoko since the summer of '68 long before the separation.
"keep the train rolling" ? George didn't want to tour or do live shows. John did a live show in Toronto when the opportunity arose. Ringo loves touring and is still doing it fifty years later.So maybe it wasn't just Paul who wanted to do a live show.
"they collaborated on one another's solo works" ? They all helped Ringo now and again, and George helped John a bit at the beginning but he soon stopped when he realised Lennon would be giving nothing in return. After that no collaboration at all between John, Paul and George until Lennon was shot. I think you're living in cloud-cuckoo land.
"perform together on special occasions" ? This is just wishful thinking. Lennon refused to do Bangladesh without Yoko. This problem would have come up again when he was back with her. And anyway, the Beatles refused time after time offers of millions of dollars to do just one show.
The clip you chose is particularly inappropriate. This interview was when Lennon was adrift from Yoko and vaguely thinking about trying to reunite the Beatles. It was too little too late. Paul was doing fine with Wings and George would never have agreed to it.