Are they really not welcoming non-Polish pilots in their corps? Are the above arguments true? or really they only seek for Polish pilots?[/QUOTE]
Foreigners are needed as they are not able to attract locals. Generally people are nice and respectful. you will always come across some old grumpy guy but this happen everywhere.
If you decide to join you need to accept that this is a polish airline , as a foreigner you are a second class pilots , you will not have same opportunities as a polish for career progression.To my knowledge at the moment there are no foreign capts on emb or Boeing fleets.
Also if you are coming from a western airline standards you may find initially difficult to fit in theyr way of operating. There is no standardization among crews and training is average , crm is poor.
Having said that is true that company is trying to improve theyr training standards but things happen very slowly in here.