What you are describing sounds a lot like my controller issues back in Destiny 1 on my PS4. I found out the hard way that my R2 (right trigger) was partially broken. It worked enough to activate at a digital level (eg: shooting), but for analog controls (eg: sparrow boosting) it was not registering the full trigger pull. I started to investigate the issue after feeling slower on a sparrow, and having a lot more difficulty performing stunts/flips. Not until I flipped the R1/L1 and R2/L2 buttons on the controller did I realize the extent of the issue. The solution was to replace the controller as it was worn out. The original PS4 controllers had a high failure rate in the triggers like I described. They fixed the issue in later versions of the controller. It's supposed to be fixed with the controllers that shipped with the PS4 Pro with the modified light bar. As your are on Xbox I can't speak to those controllers. However, it does sound a lot like my broken trigger. If you can, try swapping your boost to a different button and see if that solves your problem. If it does, try a different controller with the original button mapping. Might be time to just get a new one.