Whilst not the same vehicle or system, our 2019 Honda Odyssey brakes were doing a similar thing. It would take 2-3 pumps to get them to engage 100%. If you put the pedal down, it was like they were 25-50% of normal. Dealer did a brake fluid flush as there was a TSB, no change. It wasn't until I put new brake pads on that they finally started working correctly. I changed out the rotors after that as well. Been going good for a year now. In the future, any brake issues like that, brake pads and/or rotors will be the 1st thing checked.