Welcome to New to Sikhi community
No, being a father of a daughter I can assure no Sikh dad would.
I agree with Sardar Yusaf Singh Ji in toto. Every Sikh ought to read the 52 Hukams or Edicts of the Tenth Master. The Edict number 38 quite clearly says so.
As long as he was a decent guy who treated my daughter with respect, and respected her beliefs then i would be fine
I agree with Jason Skrzypek-Singh
If both are mature adults and are open and honest with each other, then I would have to respect my daughter's decision as a mature adult capable of handling her own affairs and making her own decisions.
If he truly loves her, then I say they're off to a good start.
If you are not a Sikh and want to end Sikhism sure let your daughters marry a non-sikh.
However those who love Sikhism, those who raise their daughters in the right way and those who infuse their daughters with strong love for Waheguru and sikhi well they would never dare or consider marrying a non-sikh man.
If a daughter of mine fell in love with a non-sikh man and wanted to marry then I have failed as a father I have failed to teach her the beauty of Sikh philosophy and faith. I would naturally not bless her marriage I would show how dissatisfied I am with her choice and I would not communicate with her until she realised how important the faith is to me and should be to her.
Give your daughters so much love and protection that they only want a Sikh man, teach your sons to be gentlemen and to respect women so that all women desire them.