Indeed this would mean my reasoning doesn't hold anymore since it's based on calorie consumption. The only thing that still surprises me, but that's no calculation and just a fact, is that you only need around 5x more joules to move a 1800kg car vs a bicycle according to Wikipedia (https://en.wikipedia.org/wiki/Energy_efficiency_in_transport) even tho the car weights >18x more.
On the matter of calorie burn staying stable, I had never heard of this before! Will be very interested in checking it more in detail as it seems like a very important thing to take into account when trying to loose weight, surprised this research isn't more widely known! Thanks for the feedback and article.