I'm in the camp of more cores = better. I'm still running my TR 3960x because half the time I'll have something like SSMS open running something with 20 browser tabs plus 4 spreadsheets etc etc and tbh I don't want to close any of it but still want epic performance when I fire up a game, therefore more cores is unquestionably better every single time. I'd take my 3960x over any mainstream cpu currently available.
on my old 1st gen i7 cpu quad core ht, iv had 25 tabs open along with word, excel powerpoint and arduino ide. looking in task manager showed cpu usage to be under 5%. ram usage was a different story. but this goes to show you can have as much open as you want thats ram dependent and nothing to do with cores unless each browser tab is opening a dodgey website that had crypto miner on the go.
if you like i can do a screenshot on my current pc with 40+ tabs open on a 5600x cpu and cpu usage will be next to nothing. its not like someone can interact with all those pages simultaneously.