While my experience with male dogs is limited ( we prefer females)I have had 2 stray males that we have kept. 1 was neutered at just under a year and the other was closer to 2 years old ( due to when they showed up here).
What I found was the older male has kept his need to mark everything and anything and I find that absolutely infuriating when he pees on my hay bales or on my females as they try and do their " business".
We didn’t have that on our other male who was neutered younger. Both dogs are ( were) a large breed.