As you said if the game got attention the developers would upgrade it. The problem here is that attention doesnt come to you, you have to earn it. To do this the game has to first, invest in new servers, make a new tutorial, implement a proffesional customer service support, etc. Even if they do this, be aware that the game has not been and is not able to adapt and compete in the video game market.
The game was growing and was even in the top 5 games rankings of Appstore in 2014 where 5-7k people were online and actively played the game. Now ask yourself why currently there are only 1.6k players online? We are not in 2014 anymore, we are in 2021. People's likes and expectations have changed and most people dont like these type of games ANYMORE. Even if this game gets advertised it might never grow. We arent being negative, we are being realistic.