Earlier quoted context omitted.
My personal experience in the field does not support your apparently strongly held assertion. Thus "IMO". > "you shouldn't try to grab focus with" Please do not question my motivation. I had a point to make.
It's not an assertion because this isn't something up for debate. Women face a lot of discrimination in the tech industry. You can say, "I don't see it," but saying it's your opinion that it doesn't exist is characterizing it as something that is opinionated. I'm sorry if it wasn't your intent to steal focus. What you did, whether intentional or not, is a common derailing tactic.
If he hasn't seen any compelling evidence of [Issue X], then for him it remains unresolved. Rather than being offended that his mind isn't made up the right way, you might consider sharing whatever evidence makes you convinced that [Issue X] is a problem.
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assertion - a positive statement or declaration, often without support or reason (from dictionary.com)
That seems like a perfectly fitting word to me.