I just want bring something underwater to take photos leh. KK I go see more reviews.
GoPro is basically an action cam....
GoPro Hero 7 black can use for underwater video as it is (I used mine gopro hero 6 for skuba diving activities at Maldives and Krabi.)
As for Olympus... I have the older TG4 model... (used as backup) and tried at Krabi but my opinion is ... it’s still decent for general usage, not for video.
GoPro Hero 7 black can take good still photos... can also do timelapse photos/videos.
Only thing about GoPro cam.... you need to bring along spare batteries coz the usage pattern is different from using a normal camera.... you tend to let it ON for most of the time.
PS - for underwater photography/videography, make sure to use a red filter on the lense... Recommended!