Actually jdramas are rocking it. I mean, the hype "Erased" got on netflix was pretty dope.
A lot of anime and manga are currently remade in other countries (mostly america) and considering that a hella lot of jdramas are based on manga/anime i would say that's pretty good, is it not?
Also, the plots of this years jdrama are pretty complexe. They tackle a lot of special subjects, which is way better than rolling with the mainstream. That's why we jdrama fans love them so much, or at least that's why I love them so much. 

The love for asian countries is just hitting the west (okey, depending where you live it might be at it's highest right now). That includes anime, manga und drama from all asian countries. So give it time. The demand for anime and manga is high, so will be the demand for jdrama. A lot of people might need some time to get to our wonderful world of dramas. Especially the anime fans. I mean, yes there are a lot of good live action movies, but until you get addicted with them, it takes some time^^
Netflix is doing a great deal to get good Dramas on their program. So patience is all we need :)

At the moment, i have the feeling that the demand is focused on kdrama, but that doesn't mean it's a bad ting. With "Meteor Garden" there are a lot of people who are now interested in chinese/hong Kong dramas. "This one's on top, then that one's on top.." like some famous dragon queen once said :D
So i really don't agree with your first statemant, but i do see why you are worried or why you wish there would be more subbers.

People siting the lack of romance as to why Jdrama aren't popular reminds me of that episode of Friends when Joey and Chandler started watching porn all day because they had an open porn channel.

 Why do you think for Asian drama to be successful it must be romantic? and who watch romance all the time?. I know its their taste but that does not mean they can measure the drama quality according to it.

and about low budget, there're many low budget movies that made a lot of money at the box of office. 

I think the main reason not a lot of people watching Japanese drama  is because they take asian dramas lightly, they're mainly interested in romance plots and good looking cast with shiny and flashy outfits or objects.  

as for older jdramas, I think it will be very boring if they repeated the same thing over and over. even kdramas started changing and produced a lot of detective and law dramas in resent years. 

if you you want that nostalgic feeling I recommend watching asadora (morning dramas).