Hi Alex,
I can not directly comment - I use them for all my windows k8s agents but that's not a huge load compared to the linux ones which have not yet switched.
However, I would rather suggest that if your instance is requiring some upgrading I would setup some monitoring (OS metrics, process metrics, and send Jenkins logs to somewhere). this will allow you to see impacts of any change you make and see any patterns before and after any changes.
After that, change one thing and one thing only and see how it works for a reasonable period (depending on your load that could be a day or a week), then if things don't work you will be able to track it to a specific plugin upgrade, or a core upgrade, or in this case switching agents to websocket.
Regards
/James