My advice is don't use the OEM 20 inch wheels, they are really bad. Very stiff, bumpy and mediocre braking as well (OEM Continenal LX Sport is very poor in my opinion). Try 20 inch from Pirelli Scorpion AS-3 or Michelin SUV CrossTek if you care for comfortable ride, road noise, good traction and good braking.
Took me roughly 2 days and test driving 3 different Odyssey and 2 different 2021 Passport to understand what you meant.
Its not bad per say, it could benefit from better tires and more sidewall. The 20x8 rims on the lower trims has more sidewall which dampers the ride and smooths it out a bit over bumps and road imperfection. The 265 (20x8.5) corners like a champ and I barely have to brake to enter any turns but suffers when you hit any pothole, uneven pavement or get near any curbs.
However using better tires and rubber to counteract that on an heavy Odyssey will only chew up the tire more.
As my Ody is not lowered and have no airlift suspensions, I felt the harshness of the road with only 2 passengers going over a speed bump.
Test drove on Odyclub members Van both airlift suspension and lower springs and shock, it doesn't feel the same, its actually pretty smooth on 245/50R20 tho the speedbump and pophole issue still apply and even more so, As I transport my family of 5 daily and for travel, ride quality is my primary concern. Will be sticking to OEM 235/60/R18. Thanks for the awesome Advice, I need to bang my head on the wall before I learn my lesson.
TLDR: 20' rims have a lot to overcome
(Joke of the Day, Honda Passport Sales was extra attentive when he guide me thru a right turn)