I liked both of those more than I thought I would.
Billie Eilish - quite a stage presence. I liked the track and I thought it was well executed, if a little minimalistic, and props for good use of pitch shifting. The drummer being behind a glass wall confused me a bit... maybe he's used to people throwing things at him?
Of the two, although Eilish had more of an "original" sound I preferred Janelle Monáe's act. Very dynamic, slick (as you say Martin) and certainly reminiscent of Prince. Maybe too much so, if people compare her to him on an ongoing basis unless she really establishes her own musical identity. She's certainly got some moves.
They are both a heck of a lot better than a huge amount of crud I've had to put up with from my two eldest stepdaughters in the past, though thankfully their teen years are now behind them and I've got 3 years to prepare before the next one starts that phase of her life