Ok I've finished the first episode now. Unenthused. It opened with the same iconic sunrise as the original, but the music and narration had nowhere near the oomph of the OG. The overall narrative didn't really pull me in as much, either, not helped by the constant cutaways to palaeontologists.

The comments in this Reddit thread already echo my thoughts far better than I could. Too many of the comments in there are just spot on it's hard to pick out a quote or two. But maybe this:

It's alright. This isn't Walking with Dinosaurs in terms of direction. Between Bartlett's music, Branagh's narration, the low angle cinematography, and the violence, the original series managed to feel like a series of paintings brought into reality. Sure, it's not nearly perfect in terms of paleo-accuracy even for its time, but it conjures a very unique atmosphere.

This isn't really Walking With Dinosaurs though. You can really tell Haines or James aren't involved whatsoever because the spirit of the original Walking With... series is totally missing. The pacing is poor due to the modern day segments, the actual dinosaur segments are largely forgettable because nothing really happens in a lot of them, the scale of the environments is non-existant and the dinosaurs don't feel like animals for a lot of the run time.

I'm still enjoying it (only 3 episodes in admittedly) and there are a lot of positives, I'm certainly enjoying it more than I'm not if that makes sense. But it feels very modern BBC, in that they're just redoing a former glory without understanding the source material

Personally, the first episode didn't really grab me enough to want to watch more. But I'm hearing good things about Prehistoric Planet, so I may try to seek that out.