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In the Milky Way, $\sim$18 Wolf-Rayet+O (WR+O) binaries are known withestimates of their stellar and orbital parameters. Whereas black hole+O (BH+O)binaries are thought to evolve from the former, only one such system is knownin the Milky Way. To resolve this disparity, it was suggested that upon corecollapse, the WR stars receive large kicks such that most of the binaries aredisrupted. We reassess this issue, with emphasis on the uncertainty in theformation of an accretion disk around wind-accreting BHs in BH+O binaries,which is key to identifying such systems. We follow the methodology of previouswork and apply an improved analytic criterion for the formation of an accretiondisk around wind accreting BHs. We then use stellar models to predict theproperties of the BH+O binaries which are expected to descend from the observedWR+O binaries, if the WR stars would form BHs without a natal kick. We findthat disk formation depends sensitively on the O stars' wind velocity, thespecific angular momentum carried by the wind, the efficiency of angularmomentum accretion by the BH, and the spin of the BH. We show that theassumption of a low wind velocity may lead to predicting that most of the BH+Ostar binaries will have an extended X-ray bright period. However, this is notthe case when typical wind velocities of O stars are considered. We find that ahigh spin of the BH can boost the duration of the X-ray active phase as well asthe X-ray brightness during this phase, producing a strong bias for detectinghigh mass BH binaries in X-rays with high BH spin parameters. We conclude thatlarge BH formation kicks are not required to understand the sparsity of X-raybright BH+O stars in the Milky Way. Probing for a population of X-ray silentBH+O systems with alternative methods can inform us about BH kicks and theconditions for high energy emission from high mass BH binaries. (Abridged)

X-ray emission from BH+O star binaries expected to descend from the observed galactic WR+O binaries