I think Fidelity's Net Benefits (which I believe is distinct from the personal site) is pretty bad though.
For an example of a thing I hate about the new web interface is trying to buy a stock. You end up in some different part of the website where after you place your order it shows you a differently formatted order status page than the normal order status page. There's an Exit button at the top. Pressing the Exit button will pop up asking if you want to leave because you'll lose all your unplaced orders, of which you have none because how you got to the Order Status page was by fully placing an order. It's confusing for no reason.
In contrast, I can do all that in one pop-up/side panel in Fidelity or Charles Schwab. I have been a long time user of Vanguard (almost two decades) and I wish they revert to their old web UI, which is informative and simple enough to get all the jobs I need to do in an efficient manner.