Forward of the firewall the C150 and C152 are completely different aircraft so anyone comparing the 2 should think again.
The Continental O-200 (or sometimes O-240) in the 150 takes it carb hot air from inside a shroud around one of the exhaust mufflers (there are two, one for the left hand cylinders and one for the right), the other muffler shroud feeds the cabin heat.
The result of this set up is VERY hot air to the carb because of the large contact area inside the shroud.
On the Lycoming O-235 in the 152, the carb hot air is taken from a shroud around just one exhaust down pipe (#4 cylinder) and as a result isn't as hot as on the 150.
Very hot air will cause the engine to effectively run very rich and the rpm to drop a lot. Possibly a muffler leak but that is easy enough for the engineers to check and I doubt the engine would be running or sounding sweet with carb air in cold.
On a Piper Warrior, the hot air is taken from around the #4 down pipe like the 152, others from larger shrouds around 2 down pipes (Archer) or a long bit of exhaust heading towards the muffler (PA28-140).
If I fly a carb fed engine I check for ice very often and for at least 15 seconds (how long does it take a hot air gun to melt an ice cube?!) - do the rest of the FREDA checks with it in hot and give it a good burst of heat if you are held at the hold for long pre-take off.
Remember, low rpm equals a relatively cold exhaust and not as much heat to the carb.
Anyone that thinks it can't be that much of a problem, get hold of the monthly AAIB bulletins!