I mean... My own experience here completely agrees with their overall appraisal of the situation.
The only reason I'm still here instead of back there is 3rd party app support...but rather than 100% of my Reddit time becoming 100% Lemmy time, it's more like 100% of my Reddit time becoming 20% still Reddit, from a computer, 20% Lemmy on mobile, and 15% in disbelief that I'm spending time on Facebook, and the remaining 45% of that time I used to spend on Reddit, I'm just not spending it on social media anymore.
So yeah. Lemmy wants to be a reddit alternative, but for me it's just not. It's similar, but with less content overall, less relevant and less interesting content, less interesting comments, and on average a worse community. Other than the shitty spez business practices (which are a big deal, don't get me wrong), Lemmy's just "Reddit, but worse in every way" to me.
Unless Lemmy gets better, it'll never be more than an occasional visit for me...and if Reddit were for some reason to right the ship, shit can spez, and reintroduce 3rd party app support, I'd probably go back in a heartbeat.