Less players use the tactical characters online, it's a fact. It's harder to use the tactical characters online because the small, but reliable timings that work in a normal situation tend to bottleneck online. You get backed up because of conditions and this causes run away for the tactical characters that is out of their normal set of tactics, ultimately reducing their effectiveness because just like rush down characters, you have to be on top of your zoning and tactical game.
It's easier for rush and combo characters to succeed inherently due to the problematic scenarios caused by netplay, ie: the rush down dictates pacing even moreso online, causing more response only commands for the defending player that become increasibly unreliable or even random. As for combo characters, they benefit due to the errors manufactured by netplay. Even with Reptile you see him turned into a combo character, which he can be no question, but you can still beat just about any character without ever breaking 50%.
As for the Cyrax inf, I run into the same problem. I tend to get like 4 or 5 air throws and then it just throws them into the center. The timing for it must either vary or have to be to the frame.