It definitely looks 3d printed, although the layer resolution is quite fine and the print quality is very good, and it hasn't been obviously damaged after 3 years in the sea, so I expect this is not printed in PLA on a home 3d printer.
Searching for "lidgard underwater camera", I found this blog post, which has more pictures but no explanation of how it was made: https://lidgardphotography.com/tag/sable-island/ - I still think it looks clearly 3d printed.
Interesting nevertheless that it survived all this time.