Indeed they are changing the reward, but is that because of people running has been low? I don't know, and I don't think anyone else outside SE does either. It's very possible yes, but there are other reasons it could have been done. None of us can claim knowledge so it's weird when people make definitive statements like "it proves the queues are too slow". Maybe they've paid attention to the forums with people saying it doesn't feel like enough. Maybe after running numbers with people actually going through against other runs the feel it doesn't align with the projected gain from other roulettes. Lotta maybes there. I know who has absolutely no idea though: The people who haven't run it more than once since the change.
I'm gonna assume you mean change. Empathy is nice, but getting outraged for someone else and speaking for them isn't great either. I don't think the jump potions were for people who didn't enjoy the MSQ dungeons in the roulette particularly, they seemed to be marketed toward people who got friends to join and wanted to adventure together in the new content instead of waiting a week for them to catch up. That's my own point of view though so once again, how can you know what they intended? I don't disagree that SE should have done something with the MSQ retroactively and smoothed it out for later patches. But asking them to revert this change immediately without seeing or experiencing it's impact, especially when most of the arguments are boiling down to "it's not enough reward for this" and "what if my alt.. " both pretty selfish when weighed against a new players first experience.
I get there are upset people, and there always will be. Someone is always not going to like how something gets done. Go ahead and post your grievance but be prepared for people to call you out if you say things like "the majority of players" or "this is bad for everyone" with no numbers or facts to back it up besides personal anecdotes. I am personally of the opinion that the unskippable cutscenes bleeding into undersized parties and solo runs is an undesirable change but if given the choice between before and after the patch I'm going to say the people missing out on the most were the people who wanted to watch story BEFORE. If you compare the options they had then, vs the options people have for xp and getting through the MSQ on alts now, I'd say this new arrangement is the better deal. I also get that this is based on my own personal values, which aren't going to change. I'd be glad to explain , again, why I feel this way, but you're never going to get me to say people who want to repeat/redo/skip something should be allowed to do it while people who want to experience the game as it was designed have to find a workaround.
People who want to experience the story will come back , again and again for expansions and patches, and new people who are the same will go back and want to experience all the side stories as well, while people who just want gear/progression will consume current content quickly and then get bored, or complain about no endgame content and leave. I think more money lies in the former.