I assume the profit margins for IR panels are much higher than for heat pumps. The former are some resistive wire mounted in a panel of some sort, whereas the latter are relatively complex machines being sold into an extremely competitive environment. I could imagine a $1000 IR panel costs $50-$100 to make, and a $2000 heat pump maybe $1000? Similarly installation for IR consists of a connecting wire and four screws, compared to pipe runs etc etc for heat pumps.
Nett result is IR panels offer high "value add" (ie profit) for the supplier and installer, so they are marketed more vigorously - just like HRV and nitrogen in your tyres.