If one does a sample study of Sikh names even upto 1920s, most of them had no suffixes and prefixes. They were simple names like Bhagat, Uddham, Kehar, Vazir, Ram, Bishen, Kishan, Arjan, Bir, Zorawar, Jarnail and umpteen such short and crisp names. Names culturally deriving from Hindu ancestry, or Persian influences or even British influences, sometimes even after names of cities and places, were common and it was a vibrant period of synthesis of streams into Sikhism. Except for names like Ranjit, one can't recall many historical names of Sikhs with such a unique grammar.
Sikh names having suffixes like Meet, Preet, Beer, Leen, Veer, Deep, Jeet, Inder et. al is a recent phenomenon, started after some trends of naming kids from the Sri Guru Granth Sahib, with the name of a kid starting from the first alphabet in a random page of the SGGS. So Sikhs pick the alphabet or a word from the SGGS, and then form a convoluted name (as my own name, for that matter), find a prefix matching the alphabet and then attach any suffix that appeals with that prefix, as long as it doesn't match anyone else in the family.
The shift it seems has much to do with the Singh Sabha Movement which started a movement to clearly dileneate Sikhs from their cultural baggage and give them a distinct identity. The evolution that is over now. Sikhs have now shifted to a distinctly different identity just by dropping all names that link them to their ancient lineage.
You won't find a new born Sikh being called Bishen Singh or Kishan Singh or Gopal Singh or Ram Singh or Arjan Singh anymore, it would almost be sacrilegious. The prefix of Inder is also dumped (no one names a Sikh child as Dharmender or Mohinder or anymore), and non-hindu God names were sorted out, listed and slowly printed into the Sikh psyche. Sikhs though still find it fashionable to use Urdu sounding names, since that doesn't threaten to subsume their identity.
Mind you, the common Sikh doesn't even realise that the current trend has political or cultural connotations, they just follow the current norms of acceptable social norms in their circle. My answer is about the background to the evolution of such norms.
A huge positive of Sikh names though is that such Sikh names are often gender neutral and are ahead of their times in that respect.
Written by Kulveer Singh