He's an overweight, middle age man who's just had a new baby.
He was in intensive care very recently and is presumably suffering the horrific post viral effects that are associated with covid.
Plus he's prime minister, that's going to tire you out.
Oh yes, and there's the Brexit deadline next week. That's a crazy lot of pressure. The workload in itself is unimaginable, but for it all to be going so wrong so publicly, that's tough.
And you've got to think that he's feeling a bit uncomfortable about the way his government handled covid. That'd certainly age me a lot.
Then finally there must be a bit of a nagging worry that he's misunderstood the whole BLM thing. Tough to have so many racist comments of yours made public. By all accounts he can be quite smart - he must be wondering if his whole Britain as great white saviour empire thing just doesnt sit right. You've got to hope that at some subconscious level he's beginning to wonder whether just because he cant see racism in the UK, doesnt mean he can just dismiss the experiences of the many people who do.
So yeah, he doesn't look well, but that's hardly surprising.