I see two common scenarios in which a 2x-200 lens could be judged:
1. As a travel zoom
2. As a reasonable lightweight replacement for the traditional pairing of a 2x-70 zoom & a 70-200 zoom. And I'm talking F4 zooms here, or variable aperture.
The LUMIX 28-200 clearly excels in the first category. In fact, it is the lightest and most compact lens of it's type in FF. And not by small margins. And, it does it with OIS. In this regard, it is a remarkable accomplishment, IMO.
In the second category, it clearly fails. IQ does indeed trail start to off at 150mm and just gets worse as you go longer, to the point where, at 200mm, my reaction is "Bummer, man." At least when pixel peeping - again, scenario 2. In scenario 1 where you are publishing downsampled images to social media, it hardly matters.
So, if PP is calling it the second-worst lens of 2024, that clearly is in the context of pixel peeping. Fine, guilty as charged. But evaluate it for weight, compactness, and OIS, it's a different story, IMO.
Comparing my copy to my 20-60 and 70-300 at F8 for a typical landscape scene (i.e, lots of field depth), I'd say it's a toss-up on the wide end. My 28-200 is a little sharper/contrastier in the center than my 20-60, from 28mm to 60mm. Of course, due to field curvature, the 20-60 has much better foreground corners, but the 28-200 has better left & right edges, and better detail at infinity. As I've said before, you can stop the 20-60 down to F11 and focus at infinity to minimize the effect of field curvature - i.e, you loose a little in the foreground corners, but gain at the edges and at infinity. So, again, a toss-up from an IQ perspective. But I don't like shooting around field curvature, and having dual-stablization can be helpful even on the wide end, so I prefer the 28-200.
Comparing the 28-200 to the 70-300 at F8 is a little more stark. The 70-300 has better edges at all overlapping focal lengths, and the center is sharper at 150mm+. So yeah, the 28-200 isn't a good choice for critical work, especially on the long end. But that shouldn't be a surprise.
And also, yes, it would be great if we could get at 24-200 with OIS that can reasonably compete with the IQ - at F8 - of lenses like the 24-105 and 70-200 F4. Sigma, you listening?