This succinctly gets at one of the biggest problems, but I want to flesh out the depths of how unsatisfying this critique is a little more:

A big problem here is that Singer's critic isn't offering any details on what the alternative is to Singer's advice to us. What does "solving systemic problems" entail for me, the regular working class person? Talking on social media about injustice? Dedicating my life to working for NPOs?

What exactly is the alternative, and spell out to me exactly how, in tangible terms, that's going to help people more than donating a significant portion of my income to causes that help people?

If you're going to engage in a critique of a consequentialist, you need to be able to spell out what they should be doing and how it better maximizes utility than their current plan.

To me this article almost feels like a hit piece on a good person who's actually trying actively to do something about the problem by someone who's only capable of pointing out the flaws without themselves offering a better plan by people who just want to talk big without actually putting their money where their mouths are.

Also, if you understand Singer as a philosopher from the consequentialist tradition, you know that, ultimately, if you showed him a demonstrably better way of using your time, money and effort, he'd be like "Good point, that does better maximize utility," and would himself make those changes. I'm pretty sure Singer is all for systemic change, but is trying to be realistic about giving the relatively few people who read him tangible, practical advice about actually making a difference. Even if he doesn't advocate for trying to make bigger picture changes, he's most certainly in favour of them if they're possible, and his advice is not, as the above commentor has pointed out, mutually exclusive with that.