I do agree that it seems overproduced, OTT and all the similar stuff people have mentioned.
However, I think after facing cancer and potential death in your early/mid 40s, with 3 young children, we can let someone off making a video that seems 'OTT'. I do wonder if some people would be as kind about the video if it was anyone else who had made it though.
Whoever you are, knowing you might die at such a young age must be fucking terrifying and I'm sure it must make you genuinely reflect and get a bit 'OTT'. If this video is the result of how she's feeling, why not?