Why on earth did he stay?

After a promising start I found it completely implausible that Tom, even allowing for his grief over loss of his lover, would hang around being abused by the repressed homo brother. It just didn't add up. The story about the homo-erotic repressed relationship has been done far better elsewhere (Brokeback Mountain and Power of the Dog spring to mind for starters)

Humorous, but slow paced and how true?

Well acted and beautifully photographed and well written - but at times a little pointlessly slow. Alright so they are in Limbo where time does pass slowly, but sometimes the photography of scenery seemed to delay the narrative.

It is gently funny, not laugh out loud, and comes across as somewhat truthful - although how many asylum seekers are billeted on a remote Scottish island rather than in detention centres with prison like condidtions.

Entertaining, but slightly misses its mark

Some of the dialogue a bit inaudible - an increasingly common complaint, are my ears fading I wonder. An entertaining riff on political expediency, media dumbing down, and tech hyperbole as the Prof and Kate have to deal and sometimes compromise with various forces with vested interests in not telling the truth.

The comeupannce of the tech billionaire both when his mission fails and in the coda 22000 years in the future when they arrive at a new planet only to discover they are a food source to the creatures there is satisfying

Ultimately though as a satire on the response to climate change it doesn't really work as eco-climate collapse doesn't have the salience that a comet appearing in the sky has.