The exact same complaints around nationality and allegiance were voiced when Rusedski turned up on the doorstep - most vociferously perhaps by a British Davis Cup player of his time.
Muguruza has far more obvious connection with Spain and her facts are different. Her surname alone would tell you that. I doubt you'd even know where Ljubljana is.
Greg's mother was from Yorkshire. So regardless of reasons for changing, he had the right too. A bit like KP in cricket.
Bedene put his roots down here and was well qualified for British citizenship. All these players, he, Rusedski etc have made their contribution to tennis in this country and ought to be respected for that. However, crude attempts at poaching foreigners - like Djokovic - with no connection or allegiance to this country whatsoever, simply to compensate for a continuing failure in the Wimbledon/LTA axis to produce home-grown players is/was shameful. It undoubtably helped to influence the ITF's change in stance on this issue and I can fully see where others who take a harder line on this issue, are coming from.
I'm still waiting to see the much vaunted "pipeline of ATP players" that Draper promised us.