Beyond the input lag due to how the game is coded and added reading difficulty from not having smooth approach circles there shouldn't really be much of a difference. Anything above 1k fps is such a marginal gain that it won't affect your accuracy. You are probably just rusty despite feeling otherwise. This game is extremely high maintenance. The ability to hold combo comes back rather fast but things like consistently SS'ing high OD will take time.
Part of the issue is that things like aim only appear to come back fast because you are diverting your focus from things like acc to focus on aim. The result is you feel like you are holding combo just as easily as you used to and it only feels like your acc is suffering. In reality your acc is suffering as a direct result of your aim not being as effortless as it once was. This is also why lowering the AR of maps can completely destroy your aim. You have to divert so much of your focus into just comprehending what is going on that you no longer have enough mental bandwidth to dedicate to aiming.
Part of the issue is that things like aim only appear to come back fast because you are diverting your focus from things like acc to focus on aim. The result is you feel like you are holding combo just as easily as you used to and it only feels like your acc is suffering. In reality your acc is suffering as a direct result of your aim not being as effortless as it once was. This is also why lowering the AR of maps can completely destroy your aim. You have to divert so much of your focus into just comprehending what is going on that you no longer have enough mental bandwidth to dedicate to aiming.