Another blue here.
Slightly disappointed to see that fans of two clubs with a recent history of being "the best of the rest" are being so hostile to each other. And not just Southampton fans, we're equally as guilty on our side.
Anyway, we've had many years of mediocrity and we're well used to being on the receiving end of poaching (think Moyes, Rooney, Fellaini, Lescott, etc).
Since Moshiri has invested in the club, there has certainly been a noticeable change in the ambition/clout of the board, promising big spending, etc. It's well documented that Moshiri has made certain promises which have enticed Koeman.
This is not to say Southampton lacks ambition, but rather Koeman is a dutch manager with no loyalty to the club, and well - it's a fickle game. Loyalty is not something which is at the forefront of the game we love anymore. It's a shame, but its part of the football business.
I hope Southampton bounce back in the same way you did after Pochetino, and see no reason why you won't. I think the smart money is on Ronald De Boer. Can't see Emery moving (promised increased funds at Sevilla) and Diego Simeone/Ancelotti is pipe dream stuff. Pellegrini is in the market, but is known to be after a final big pay day and seems a pretty uninspiring choice.
Anyway, good luck in the hunt and we'll see what happens with Koeman - we may end up having him poached off us in a year or two!