Well, yes and no, depends where you measure. Assuming there's some resistance in that circuit (because if not, the circuit is meaningless!), the PF as seen by the source will go to 1.
If there's no resistance, then at resonance, reactive power goes to infinity while real power is still zero, so you have a \$\frac{0}{\infty}\$ form. Since it's symmetrical around resonance, the limits match and the result is zero (as noted above).
You cannot synthesize a reactance from behind a FWB though, and you'll also have a hard time doing so in front of the FWB by using lossy devices (transistors can only switch or dissipate power, they cannot produce it). Note the definition of reactance is that it alternately consumes and returns power to the circuit!
This does mean you can synthesize a reactance by using, say, a nice compact capacitor, a switching converter, and a controller to set the voltage and current accordingly (within some limited frequency and energy range, since the capacitance stores energy inversely to the desired inductance; this is quite doable at a fixed mains frequency). But that's a rather worse solution than what would satisfy your underlying problem.
(Such solutions are actually useful, though -- when absolutely required. Such a device can be used to effectively multiply a capacitor, allowing one to implement a filter that would otherwise require, say, a lot of bulky electrolytics. The Google Little Box contest winner (2014) used such an approach. Similarly, industrial equipment can be power-factor-corrected by bolting on an inverter and controlling its current draw inversely of the attached load, thus using its supply (DC link) capacitor as PFC storage.)
Tim
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