Absolutely, horse racing is already faded away even though few casino have that game option on their site, it does not really get the traffic they expect compared to other sports. If one must gamble on a horse, one must know the capabilities of the horse before betting so as to be on the safe side. I believe this is one of the attributes bettors look out for before they attempt such game but in a situation where they do not have clues just like the football where you already know the capabilities of each team and their players, you could be able to predict the winner of the game based on what you have seen them do before but the horse race is likely not that same pattern to go with.
As you have said, horse racing seems to have faded away and possibly the youth gambling population does not really look into it to giving it a try. Maybe just a few try it out and majority of the elderly who see it as fun to do. Like in my country, I have never heard any youth talk about horse racing before not to think of they betting on it. Even casinos too do not really look into that direction too. Every one wants to flow with the trend to be able to serve their clients to maximum satisfaction.
Horse race was the offline gambling still available in many countries specially in the Asian countries.Even though many online casino and gambling was exist in all the countries,the people still had their interest in the horse racing.The interest and popularity of horse race was reduced because of the game fixing become a common one.So most of the gamblers are forced to loss the money without any reason.The game conducting people should clear the black dot on them to get the market to the horse race again.The horse race also involve of big money,So the gamblers with less money will use of online gambling as compared to the horse race.