Never said it was necessarily cheaper.
Still don't get how natural gas is SO much cheaper - especially in Calli - than electricity. That's like a factor of 7.5.
On the topic of natural gas emissions vs electricity emissions:
A kWh of heat from natural gas emits 0.185kg of CO2.
So that means every kWh from gas emits basically half what a kWh of electricity emits.
Given that gas dryers use slightly more energy in heat than electric would (mainly due to the water vapour in the combustion gases increasing relative humidity slightly slowing evaporation slightly in turn), my guess is still that a heat pump dryer would be more environmentally friendly.
Less so, of course, so much longer until you offset.
To put some numbers to that.
There is one dryer I know that's available in all 3: The Electrolux TD6-7.
That dryer is basically the same size as the Miele, but only states usage for its lowest fill volume which would only equate to 6.1kg or 13.4lbs respectively.
Let's take the 4.5kW electric version, that uses 3.11kWh for that load, taking 40min.
The gas version uses 3.67kWh of energy, taking just 30min (but has 7kW of heating, so significantly more).
The heatpump version uses 1.28kWh and takes 42min.
There, the savings are in kWh 59% or respectively 65%.
In the US, the electric dryer would emit about 1.14kg of CO2.
The gas dryer would emit 0.57kg, so basically exactly half (assuming all that energy would be in gas, which is close enough given the fan and drum motors are rated at just 0.3kW together).
The heatpump version - with todays energy mix - is already more environmentally friendly at 0.47kg.
And there's the second point I often face in these discussions:
Eco options never start out cheap. And of you don't force companies to change that, they won't.
The argument in the original video goes against the new energy label makeing anything else than a HP dryer basically no longer viable in the EU and how that's not actually eco friendly.
We have basically no natural gas dryers in homes - like literally basically none.
So going with a HP just always made sense - as long as prices were reasonable.
And they didn't start out that way. A decade ago, a heat pump dryer was still only useful and made financial sense if you dried a certain lot.
Now, they are basically just as cheap as normal condenser dryers were back then.
How? Well, if you give a company a reason for a race to the bottom, they will find ways.
If they don't have to do research, they won't - why spend the money?
I GUARANTEE you that all US appliance manufacturers - especially Whirlpool - LOVE the fact they can sell you an appliance they did not have to majorly engineer in several decades for the same price as the matching washer they had to completely redesign several times.
The one reason there are reasonably priced, fast full sized heat pump dryers on the US market is probably the combo race.
If you already have a working airflow, compressor and drying profile design, you might as well stick that in a full size dryer.
That you can get such a dryer for basically the same as the "one model up" gas model from LG is still a small wonder in my eyes.