The change made it so less effort is required to maximize your score, it didn't make it so that gearing is irrelevant.
Not having to take several hours to get a good run in is not in any way "minimizing your investment' to paraphrase. If others are doing more than you now, it's because they're more geared, have better mods or have better strategy.
The reason you were better before is because you put in more time to get the better score. This doesn't make you better, just more determined. If your team was actually better, you'd still be getting better scores.