We just got a brand new Samsung Galaxy Note10+ in our lab, and we've found a strange thing about its charging situation. In short: the Note10+ charges faster with the screen-off then screen-on, and it charges incredibly slow when the screen is on.
(Non-PPS) USB-PD Chargers


Most PD chargers without PPS support can charge the Note10+ (screen-off) at around 14W(9V/1.6A). However, they can only charge the Note10+ (screen-on) at an abysmal 5W(9V/0.6A).
(PPS) USB-PD Chargers

PD chargers with PPS support can charge the Note10+ (screen-off) at around 24W depending on the charger. However, they can only charge the Note10+ (screen-on) at around 9W(8V/1.1A) similar to the non-PPS PD chargers.
Summing it up:

For reference, with the Note10+ inbox charger (TA800), the old Galaxy S10+ charges performs normally at round 14W both screen-on (14.9W) and screen-off (13.2W).
We are looking into the matter. Stay tuned!