We would really like to see an n scale Thomas.
As there is an N-scale (1/150th rather than 1/160th scale) Thomas & Friends already out there from another company, Bachmann might not have the rights to make one, as the other company might have exclusive rights. :-\
Thomas the Tank Engine ain't something about whose scale I would be too worried.
Tomix sold a Thomas with Clarabelle and Annie many years back. I have it. Supposedly, it is not easy to find it and it is out of production. There may have been some other pieces, as well, There was some complaint about gears' splitting or something like that, but I can not remember, now.
It is something that is good to have at public N-Trak shows, as it will draw the children and the parents with them. Before the Tomix set appeared, I made a Thomas from a bubble stuff toy and an old Atlas 0-6-0T chassis. I put N scale wheelsets on Clarabelle and Annie toys and there was my Thomas train. To the trained eye, it looked awkward, but the children did not notice it. All that they saw was Thomas. You did have to set the throttle on high to keep the thing running, but, again, the children did not notice the difference.
B-mann does sell Thomas in other scales. I would have a hard time believing that it could not sell it in N scale. I would expect that the licence is good for any scale. I suspect that it has not appeared in N scale because you do not want to give small children something that small as there are hazards involved and it would break more easily as children tend to be ham-handed. That is not a criticism, mind you, it is just the way that things are.