I could see how being redirected to liberal causes could feel like dismissing your concerns. If you bring bring up an issue that isn't being talked about, and people react with "oh. yeah we're already working on that - wanna join?" it might feel like they're more interested in you joining their cause than in the issue you're raising. After all, they haven't been talking about the issue you raised, so how can they say they're already working on it?
The reason is that the left is fighting for all kinds of issues, and when different groups talk about the issues they face, they start to see common themes.
Conversations like "people hate you because you're gay? People hate me because I'm lesbian!" end up with people working together under the same banner, despite the unique issues that each group faces. As more groups voice the issues they face, they find solidarity in existing banners. For example, being trans is completely different than being gay or lesbian (it's not who you're attracted to, it's who you are), but gay/lesbian folks heard trans issues and said "lots of that stuff is what we're already working on - wanna join?" This wasn't dismissing trans issues, it was making both voices stronger. LGBT folks unite under the same banner, and issues for one group are issues for them all (do not try to minimize trans issues to someone that's gay/lesbian).
The fact is that men (specifically cis het white men) are relative newcomers in the "getting shit on" world. This is NOT minimizing the issues we face - they're real and should be taken seriously - they're just new (see: women got the right to vote about 100 years ago). Folks on the left offering a "mission" are not asking you to ignore your issues in favor of theirs, they're saying "oh dang that's messed up. Add it the list, let's go fix this shit." I really like that dang dad's focus on solidarity - We fight for them. They fight for us.
yeah well it seems that the left is rather fixated on blaming men (specifically cis het white men) as a collective, even men who fit in the marginalized identities that they say they want to protect, rather than saying everyone is getting shit, so lets work together to fix it.
Also an understandable reaction. The left often talks about "systemic" problems - things not caused by an individual, but by how things are set up. It's not hard to see why men as a collective would be blamed for systemic problems - after all, only men could vote up until 100 years ago. But the left is realizing that it isn't cis het white men that were the problem, since they're also getting shit on now too - it's the rich. It's always been the rich. And that's why we're seeing "no war but class war."
To be clear, there are still folks talking about men as a collective being a problem. My only advise is to mentally correct "men" to "the stereotypical men with traits that this person thinks negatively of" and not take it personally.