Uninstalling already wipes the data and AFAIK the app must be automatically killed for the apk to be removed.
However, some apps leave some residual data in the storage area the user has access to, but all would be gone with a factory reset.
OP's issue is probably simply more resource-hungry apps and/or some Android version upgrade. Yes, some official Android upgrades for a device can cause performance issues, because it may have higher system requirements than the previous one.