there are inherent risks with NOT neutering, in the same way that having sexual organs creates issues for us owners. That you can only get breast cancer by having breasts, or testicular cancer if you have testes,etc. is what vets argue from what i've heard.
There are greater risks for bitches because of first and foremost its very easy for them to get pregnant and so have to be kept in for a good portion of their season (don't risk taking out a bitch in heat and expect to be able to keep a keen female and male apart! especially the bigger breeds!). It happens very quickly and its also not fair to any of the males to take out a bitch in heat, so be prepared for having housebound mutts and hosting other bitch play-dates. Also entire bitches run the risk of high fatality rate pyometra, i'm not exactly sure of the stats but once a bitch has this they can die extremely quickly, and expensive emergency surgery is the only hope of saving if it works.
Good reason to keep both sexes unneutered until fully matured, some vets will say one season, others two, others for big breeds not until age 3.
I have to say i have never witnessed ddogs hanging around house of bitch in heat, but maybe you are talking about when there were many strays and letting ddogs roam free was more commonplace and less traffic. I do know that if a male so decides some will run a very long way on the scent of a bitch, whether in season or no. Mostly males under good control can be managed either entire or no, any on here that keep stud ddogs would be able to testify to the difference between their males' behaviour around other bitches.
Keeping either sex is an added responsibility when entire, but a bitch who may suffer repeat phantom pregnancies, heavy bleeding, severe mood swings,and having to find other ways of entertaining during what can be a long two /3 weeks indoors, is a lot more work.
Having said all that, i completely understand the vets push to neuter and keep the ddog population to a complete minimum - too many rescue homes, but i think thats down to responsible ownership and those that don't know how to do that, or can't, should always neuter imo.