IMO OQ only worked because there was a minority of players who were willing to Flex and be selfless for the majority who didn’t care about swapping for others, basically babysitting for stubborn (mostly) DPS players.
The game is now 4 years old, it’s very common for people to stop playing the game over time. I doubt that all those people on your friendslist stopped playing simply because of RQ when QPC was available and OQ ranked also was added shortly after.
If they don’t like the queue times they could simply have simply not played RQ.
Because OW is an IP that has so much potential, people want PvE, people want movies, people want an animated series, people want comics etc. It’s about delivering on something that there’s a big demand for. People love the story/lore and have been begging for more ever since the game came out because of the cinematics and characters.
That has nothing to do with PvP becoming less popular, it has everything to do with people wanting more Overwatch, something the DEVs have not been able to deliver.