DQ serves "more people" because it's in favor of groups.
It serves more people as it works for solo or a group of size. It's simply a better choice to have a flexible queue than being forced to play solo or have a full team of 5 players. SQ only served two opposites of the spectrum while DQ serves all of them. SQ was limited whereas DQ is not.
And for cash grab, trust me, people buy things just because they want to feature it on their YouTube channel.
I don't think you understand how business works.
Redmercy, for example, spent 500$ for 320 Hextech Chests, because he wanted that Hextech Annie he doesn't even freaking play or will use in any point at time. But he really, really, really, really wanted to have the skin because not a lot of people would get it. So, a high ELO assassin player spent 500 bucks on something he'd never use and doesn't sound fishy to you?
Before this Red's business endeavor, to my knowledge he didn't have 1 mil subscribers and none of his videos have ever had a million views. And yet, his $500+ HEXTECH CHESTS OPENING generated quite an influx of subscribers and that video alone sits on 2.34 mil views and all of these people have also given him a lot more views on his future videos. He spent 500$ on League's loot boxes and it looked stupid from our end but he made up that sum quite easily from hi YT channel from this video alone. And he still enjoys the benefits of this smart decision.
https://socialblade.com/youtube/user/redmercy
Click on this link and scroll down to the bottom of this page and see his channel stats. His video was made on 4th of April and that spike on the graph is his monthly viewer count for April generated by this video alone.
The graph below this one is his subscriber graph and there's the same spike during the same period of time where he has gotten a shit tone of subscribers, off that video alone.
This is all a business strategy. He has made more money than he spent on chests he didn't even want.
Since his video, every major YTber that's more or less on League's map has done this, either at once or payed smaller sums multiple times, and it was all for the views and getting payed more. Riot didn't pay them anything for such an advertisement, they did this on their own accord. They all spent money to make even more money out of us. I wouldn't call them cash grabbers either because this is their job and they're getting payed for it. Riot had nothing to do with this and their own advertisement of Hextech videos also made Riot money. Large TYbers advertised buying Hextech Chests which made Riot money and they have made money off these videos alone + in the long run of their channels.
Remember when PBE was for testing and not showing off new skins?
PBE is an environment that exists for testing bugs or values of certain changes.
Bugs exist with new skins as well and everything has to go through PBE in order to reach Live servers. Don't blame Riot if people only want access to PBE to play with new skins only and are not interested in any champs that have gotten a buff or a nerf. But then they come and cry on the boards when a bad change goes through and who's fault is that?
Riot didn't get proper feedback from the people who apparently care but were too busy with testing a new skin they'll likely never use. People are dumb and they missed the point of the PBE. Perhaps such people should take heed from my post and actually use their PBE accounts to actually test changes that they think are good or bad.