I am sorry to hear that the load time is slow for when you are updating your products. I'd be happy to help you get to the bottom of this.
May I ask if you are using the bulk editor to update your products and/or if you are updating products via the Google or Facebook sales channels? The more details you can give me, the better I can help. This will help us narrow down the issue further for you.
A lot of the time, all that's needed is to reset everything and perform some troubleshooting steps to see if you can replicate the behavior. Can you please try these steps below and let me know if you are still experiencing this problem:
Sometimes trying the steps above is exactly what is needed to get you back to business in no time!
Let me know how it goes.