I agree that most of the locals are drawn to the London clubs and the obligatory LiVarpool and manure. I’ve been in the local CIU Club when the local manure supporters coach has arrived back from a HOME gameTo be honest I only use Stevenage for B&Q so I can’t profess to be an expert.
Quite a few of the local lads from the villages support them but often as a 2nd team. It’s mostly Arsenal and Spurs with some West Ham and Chelsea thrown in or Watford/Luton for those who actually chose their nearest team rather than nearest good one when growing up.

My wife’s family are from the Old Town area which I like, good selection of pubs and eateries but while the younger family members do go to watch Stevenage the older ones have probably only been there a couple of times.