IE hasn't worked on my PC for a while now as every time that I click on in it, it sends me to Microsoft Edge. I'm still able to download items from the store as well as using the launcher as I'm still on patch 1.67 even though I don't use the ITF disc to start my game. I haven't had to use that disc since I had reinstalled my game back in 2015, a year before the 1.69 patch came out.
Edit to say that even though I have Edge on my PC, I use Google as my search engine.
Edited again to say that there is already a thread that was created by another Sims 3 player wondering the same thing as you.
https://forums.thesims.com/en_US/discussion/989900/microsoft-is-retiring-internet-explorer-will-this-affect-online-services-of-ts3#latest
