A little clarity might help.....it's not so much that a manager, in this case Villa's manager, should pursue another club's player, but it is an altogether different proposition when, in a relatively short space of time, the reported targets of this club are then pounced on by Villa's manager so shamelessly. You might call this coincidence, but that's so far off the mark when Wilder's targets are then pursued by Smith. In other fields this would be called plagiarism, but in footballing terms this amounts to theft on a grand scale. No hard work necessary, just follow another manager's lead and you know they'll be a safe bet in terms of quality.
It might be easier, as well as cheaper, to invite Smith over to Sheffield for an afternoon where he listens to Wilder and his team, learning how to spot players, how to identify relevant talent, and how a Wybourn Kiss can sometimes cause offence.