Supposedly Big Bird is about 10" tall. That seems about right for 1:10 scale, which is what I think they are going for.
You know, there is this weird thing where I genuinely hate math, but when it comes to calculating scale and size of figures, I suddenly become interested enough to muddle through it. Perhaps if they taught math in school with action figures, I wouldn't have hated it so much.
In any case, I don't think this line is 1:10. Besides Big Bird (8 feet, 2 inches) and a couple of other characters, it is really hard to find "in-universe" heights for many of Muppets, but given various sources, it seems Ernie is supposed to be less than 3 feet tall (around 32 inches or 1/3 the height of Big Bird) and Bert is about 36 inches tall.
If Ernie's figure was 1:10 scale, it would be about 3.2 inches tall.
At 5.6 inches tall, the figure is closer to 1:6 scale.
If Bert's figures was 1:10 scale, it would be around 3.6 inches tall.
At 6.5 inches tall, this figure is also closer to 1:6 scale.
So, it seems that these guys are bigger than 1:10, though the ratio is actually rounded, and of course this based on characters whose heights are tough to nail down. Look at it another way, the DST figures were intended to be true 1:10 scale, and these guys are a heck of a lot bigger (as are the Palisades and Boss Fight figures).
So, if you use 1:6 scale, the Big Bird figure should be 16.3 inches. Alternatively, if you take the fact that Ernie is intended to be 1/3 the height of Big Bird as true, then the Big Bird figure should be 16.8 inches.
I think either way, this figure is going to be undersized (if it is really 10 inches), but as long as it looks good relative to the other figures, most people (including myself) will be happy.
