Although many are anxiously awaiting the forthcoming release of the Shadowkeep expansion, plenty of Destiny 2 players are enjoying the content currently available in the game including Season of Opulence. That said, it is by no means a perfect game, with the community having a ton of requests including the ability to ride Sparrows on Mercury, bad luck protection on sleeper nodes, an easier method to unlock forges, a fix for the Reckoning drops, and more.
Now, a Destiny 2 community manager dmg04 has clarified why such QOL requests take so long, specifically using the lack of sparrows on Mercury as the prime example. dmg04 first reveals that the feature was once in the works at Bungie, but it would cause some game-crashing bugs or have a negative effect on some Mercury activities. This meant that Bungie had lost development time that could have been used for other content.
Bungie made the decision then to put the Mercury sparrow QOL request on the backburner to be looked at again in the future, since the time wasn't there to fix the various issues it caused. While the simple answer seems to be time and priority, dmg04 put it as "each QOL request has a trade-off." Instead of working on adding Sparrows to Mercury, the time could be used to work on other details such as the Dreaming City curse cycle, which had a more immediate impact on Destiny 2 rather than fixing old content.
The approach to oft-requested QOL requests is based on three factors, according to dmg04. Requests are prioritized by community feedback, release timelines, and available workers, meaning that Bungie has to prioritize content for Destiny 2 based on a variety of factors. It's also worth mentioning that, while some may prefer QOL improvements to new content such as the Bad JuJu quest, Bungie also likely has to consider how many players want what (based on community feedback).
So, while Destiny 2 players may not yet be able to ride Sparrows on Mercury, it's likely because Bungie has something bigger and better in the works. And considering Shadowkeep is reportedly similar in size to Rise of Iron, players will likely reap the benefits in the coming months.
Destiny 2 is out now for PC, PS4, and Xbox One.