Yes, what I came on to say! ADHD is highly genetic - there is an over 70% likelihood one of you has it. (In DS1's case, it's me, but I do wonder about his dad as well since he can be extremely reactive and impulsive).
Secondly, I don't think the conflict avoidant parenting style works well for ADHD. I totally get where you're coming from because this is my default as well. But it is actually important for children with ADHD to have clear and consistent boundaries, possibly more so than for neurotypical children. They won't automatically navigate and work out where the rules are like an NT child would. I don't know much about ASD, but I think the same is likely to be true. On the other hand, the overly authoritative, do as I say right now kind of parenting that objects to "backchat" is also unhelpful, because this also relies on a set of universal assumptions that the ADHD child is unlikely to be able to meet, and an ASD child will often fail to pick up on at all.
Have a look at Janet Lansbury - she has some really good stuff about how to set clear boundaries in a way that isn't dominating and controlling, but is still clear. She explains some of the problems with common "gentle parenting" type advice in here as well which I think if you're conflict avoidant you tend to be drawn to (I know I am) but it doesn't help because the advice is all about how to avoid the issue of the boundary rather than just addressing it in a fair and calm way.
Another issue that tends to occur when you have one parent who leans towards authority and one who leans towards avoidance is that the authoritative one fears that the other parent is "too soft" or lets too many things go and therefore as a reaction they are even harder on DC. And meanwhile the avoidant parent fears that the other parent is too harsh and will crush DC's spirit and so in response tends towards being even more lenient and understanding hoping to cancel out the effects of the other. You will not get to a healthy place like this both pulling against each other. You can work better together if you work on how to enforce boundaries in a way you're comfortable with and if he works on empathy and seeing the situation from DS' perspective before he starts. Which might include investigating ADHD for himself.
I'd recommend to you: Janet Lansbury's podcasts and Facebook page.
I'd recommend to him: the book Smart but Scattered. There's an executive function checklist in there for all ages of children from 4-14 and one for adults. The adult one should immediately flag up if there are issues of potential ADHD.
For both of you, something like the whole brain child or no drama discipline would be good, if you can read something like that through together. It should appeal to both of you in different ways and help you work together/lean in. You obviously have things that you respect about each other; try to find that in parenting and find your common ground, then learn from each other and see where you go with it.