Lower Wattage on MacOS Ventura BT

I am using Elite Suito with Wahoo BT/Ant HR connecting via BT to Macbook M1 Ventura. I moved from windows desktop with ANT+ connections. My Cycplus ANT+ dongle worked flawlessly since last 3 yrs on windows.

I moved over to Mac 1 month ago, my ANT+ dongle just looses all connections in 10 min & then never connects back unless I restart zwift. I may need to invest in a garmin ant+ dongle but worried if that may go to waste.

So I shift to BT as a fall back, but with BT I see the power wattage lower. I connected my garmin vectors pedals to check & it confirms my suspicion. My power is at least 20% lower. Apparently at lower wattages(<120W ) on garmin vector, zwift reads them as 80-100W. But as I put in more power, difference is increases. When I am putting in 200W garmin vector, the reading on zwift is 140-150W. When I put in 250-300, zwift records 180W. I generally use zwift for trainings or riding with robopacers & I am a just hobby cyclist. Both of these are getting impacted. e.g. when I start riding with Bernie, I need to put in 2.0W/Kg to keep up with the 1.4-1.6 W/Kg robopacer. Anyone who faced this managed to resolve?