I was asked by Blizzard support to post here about this issue to see if I can help anyone with this and help Blizz get more info on this since they feel it’s possible this may be an underlying issue with as they said " It’s possible that an update with our patch or a recent update with Genie/Bonjour has been causing conflicts with Overwatch, with the result of the SIM spikes. With the recent PvE disconnection reports, we suspect something between Netgear and Overwatch may be causing these similar reports.
The issue is this: Without going into the minute details of my situation, the Bonjour service which is typically something installed with Apple products and installed with the Adobe Creative Cloud app for all platforms, was severely impacting gameplay by causing what I thought were lag spikes and a networking issue (Huge SIM spikes on the ntegraph in game but also actual ping spikes too).
I found Bonjour to be the issue accidentally by trying to install new Intel driver updates, having the update freeze the comp, checking the Windows event viewer to see what happened, and I saw tons of errors from Bonjour that have been happening for a long long time. I uninstalled the service and like magic, the game was super smooth once again.
How Netgear comes into play: I had a Netgear router. I built a new system with this old router in December. I also decided to install the Net Genie software along with it which i never had installed prior. This ended up being right around the time I noticed the “lag” in game. Bonjour, according to some posts on the Netgear forums, has been an issue for a while apparently conflicting with either netgear routers or the Genie software itself, I can’t be sure on that one.
I just bought a new Linksys router a few weeks ago. Issues persisted.
SO, with all that said, if you are experiencing these types of “lag” issues and there are SIM spikes along with your lag, check to see if you have Bonjour installed and uninstall to troubleshoot and report back here.