What is he actually doing with his time?

Is he using his free time to give your kids really quality interactions and opportunities and time that he couldn't if he worked full time?

Is he keeping the house well and doing repairs and touch ups and cooking so you all have a good place to live?

Is he volunteering or practicing a hobby he's passionate about?

.....or is he sitting on his ass playing video games or goofing off on the internet and just wasting it?

That would be the decider for me.

There are people who can legitimately earn a full time income with part time work. Or people who arrange their budget so they only have to work 10 hours a week because that's their priority.

A few years back I got a job that paid twice the hourly rate of my old job, so I was able to work half the hours and spend more time with my then toddler.

Working a full 40 hours at a job isn't the pinnacle of achievement.

But if you get that kind of opportunity, I fully agree you should be USING it for something.

If he's taking advantage of this to benefit your family or volunteer or something- then I'd say this is worth working through in counseling.

If he's using it as an excuse to be lazy? That would be a huge turn off for me as well.