Maybe the Google Takeout batch is too big?
In my setup I have a largish 1500 images + some movies 3.5 GB Google Photos album. The last time I tried, I had to break it into smaller batches because it did not download as one.
And BTW lately I have had to use Firefox to upload larger (more than 2-10-) image batches to Google Photos because uploading with Safari nowadays very often stalls at some point.
Anyways, this question should really go to Google because it is their product.
p.s. If you have done any important metadata edits in Google Photos, and want to preserve them, use GraphicConverter or exiftool to join the .json sidecars to the images and movies.