That is such an old "standard" procedure. We ( West) used to fly Phantoms into East Germany to see how long it took them to respond - then switched on the afterburner and disappeared. The Russians have done that in Norway and Finland for ever. Old news.
With the small caveat that there wasn't a hot war with the party doing the peaking in progress one country over. This is literally begging for an escalation and that's most likely the only reason they haven't got one yet, not for lack of ability. The amount of hardware on NATO's Eastern flank is pretty impressive, especially in NE Poland and the Baltics and Finland near the russian border. Those pilots must have been wondering if the lack of response was good or bad news.
