That is the thing though. The game has to have a relative market to focus the title to and meet the bottomline.
I'm not knocking inline because I know it does have a following and a good number of those involved would buy it.
However, even with other niche crowds thrown in there it'd be a tough sell to a publisher.
Something like THPS did so well simply because it also allowed the Platform gamers to get involved.
Personally, I think a sim inline game would be fun, but I don't see it even remotely hitting a Platinum status in sales.