As someone who attempted a new run for the first time with no prior knowledge, I can say that reading about and comprehending the IGT was not very difficult. The only thing I think could improve is having a link to the resources page from the rules. Getting the igt timer to work was as simple as putting the xbe in the same folder as the game's default xbe.
The main detractor from running the game isn't the requirements to be allowed to post a run, but the game's gameplay itself. Coupled with its unavailability and invisibility on the market. JSRF is better enjoyed casually in my humble opinion. Though, then again, you could say the same about most games. But JSRF in particular has finicky controls, and the graffiti camera can be devastating to those who haven't put in the practice to circumvent it.
Asking people to run an in-game timer that is as easy to install as copying one file and then using it with the emulator you already had to learn to use is not a big ask when literally every other game requires OBS and Livesplit.
To record my run I merely had two install 3 items. 2 of which would have been virtually mandatory for all other games to begin with.
I appreciate your concern. However, I think the best way to make this game grow is simply to tell people about it and spread the word it even exists. If the game resonates with someone, they will jump through the one or three hoops they need to go through. :)