The statement isn't wrong, though.
Of course, the difference is money, no question about that. Lemmy has two underpaid devs. Reddit probably has a hundred. Lemmy instances are hosted as cheaply as possible, while Reddit has a massive budget for that.
But that doesn't change that there is a real difference in quality. My Lemmy instance (feddit.de) frequently throws errors about being overloaded when I try to access it. Can't remember that ever happening to me on for-profit social media (I guess, except of Twitter, which I don't use. But Twitter can hardly be counted as for-profit by now. It's more of an involuntary non-profit.).
Search and SEO are pretty bad on Lemmy. There are frequently desyncs in federated content. There are lots of small and larger bugs in Jerboa or the Web UI.
UX isn't great. There are many things that still need to be sorted out.
And yeah, all that is annoying, but me as a tech enthusiast have the patience to power through it.
But if I'd convince my wife to use Lemmy, she'd probably end up throwing her phone.
For non-technical, non-patient people to use Lemmy, it will have to improve quite a bit, and I believe it will maybe get there some time. But it's gonna take time. And probably, we as tech enthusiasts will have to do something we really dislike to do: Pay for development and hosting somehow. Freeloading only works if there are ads and enough people who don't know what an adblocker is. That's not the case here, so long-term, we'll probably have to pay for something here. (e.g. here https://www.patreon.com/dessalines)