Cumulative sexism

[Feefifo9]

I had an argument with my husband.
Someone we have been dealing with was meant to be organising something (in a work capacity) that directly impact us in a major way.
I had expressed clearly my concerns about the way they were approaching organising it, laid out the potential issues and how they could do it to avoid these issues.
This person ignored me.
All the problems I foresaw have happened and the impact is quite major on us.
I expressed my anger to my husband that I felt because I was a youngish woman, and this person was a middle aged man he dismissed my concerns and didn’t seriously consider that I could be right or I might know more than him. That I was livid because of the cumulative effect of sexism and I was worn down from it.
My husband said I should take each person individually and I wasn’t justified in being angry because of how other middle aged men had treated me.
Is he right?
For clarity, I was venting to my DH and was polite to the person in question.

It’s structural sexism where women’s voices aren’t heard. Plenty of businesses are becoming more aware of this issue but it is a very real problem.

Story of my career as a young woman in the corporate world. It wore me down and I left the corporate world.

I now genuinely find it perplexing that middle aged men are in charge of anything - in my experience it is the cohort most likely to be incompetent.

This isn't a supportive reaction from you DH. Of course it is impossible to know if this specific instance was due to sexism, ageism, or just someone being pig headed and stubborn (or, quite possibly, a combination of all three). But your DH had a choice to either A) sympathise with your feelings, acknowledging the probable truth in your assessment of a situation that you have a perspective on based on your lived experience which he cannot possibly share or B) choose to pick an argument, which minimises your real experience and completely fails to address your sense of frustration.

So I can understand why you are annoyed.

I was literally keeping our company going when I was in my twenties and my 50-year-old male boss's eyes used to actually glaze over when I spoke to him. He didn't even try to hide it.

It's vile. I left and work as a contractor now making multiple times over what he made.

OP, look up structural violence, which is similar to what you describe.
Did you lay out your objections in writing? Always useful to be able to back up your "I told you so" with written evidence that you had anticipated the problems and been ignored. What's being done to make recompense?