Not to let facts get in the way of a good story or anything, but there are a few things to keep in mind:
Only a portion of the B44's catchment area (and ridership) is reasonably within the subway's catchment area.
Accessing public transportation, reaching your final destination, and making transfers all require walking. Walkways have varying widths, and some people move faster than others. To add to this, people typically opt for convenience, meaning they are far more likely to push for something that involves less walking.
If I'm not mistaken, you discussed elsewhere how differing schedules can leave a negative impact. While it may have been in reference to operations, it nonetheless also applies to passenger connections, and that includes diving between a higher combined frequency and a lower singular frequency that is approximately half of the previous one (and with intervals that are greater than 5 minutes, to boot).
Any sort of rail connection between Franklin Avenue and Crosstown will basically need a guarantee (not a mere projection, but an actual shift) that it would be used in significant enough numbers to justify restoring the second track, having full-length platforms, and establishing the rail connection.
That implies that the trip would be time-prohibitive, which it would be if all northbound buses used New York Avenue (as the pre-SBS B44 ran). That, however, is not the case, especially since Brooklyn's streets are generally nowhere near as shit as Manhattan's.
The rail systems of Brooklyn and Manhattan are rather accommodating, whereas the only areas in NYC Staten Island really cares about are Manhattan's CBD, Bay Ridge, and maybe Downtown Brooklyn (extremely unlikely to change anytime soon, so don't bother). By stark contrast, the Bronx network is rather limiting (all trains go to Manhattan, and all but the are rather north-south within the borough), and the Queens rail network is pure shite. If we're to focus on increasing rail service to LIC, we need to focus on these groups -- especially the eastern portions of the Bronx and Queens, which have especially poor cohesion with the rest of the larger network. Yes, there are improvements that can be made in Brooklyn, but that borough already has the easiest time reaching LIC.