re: Why are 401k platforms so far behind other retirement plans?

Yeah, I hear you. Probably still to keep cost down, but it is frustrating. I got to the point we're I'd make my own spreadsheets to sort the horrible offerings because the functionality was terrible. Not to mention the fees!

My previous employers used Transamerica and Mass Mutual. Both had horrible interfaces.

I'm on my own now and use Vanguard and Schwab. Both much better but still both could use some better query/sorting options.