Depending what all the other effects you describe do to food production and communicable disease spread "we'll all be dead" may be only a moderate exaggeration of the effect over say a century or two.
That's my point, without more information that doesn't make sense:
1. I don't doubt disruption in global food production will likely cause some famines, but again, plenty of places will still be able to grow food, and in fact many places will open up to food production.
2. I don't see how any increase in communicable disease spread leads to anything close to "we'll all be dead".
Yes, lots of people will die due to the impacts of global warming, but nothing I've seen says there is any reason to think it will be a species ending effect.
As we are under more pressure due to all the factors you pointed out the odds that we are able to avoid spread of a highly contagious virus with a higher fatality rate than COVID (closer to say MERS) or a series of big famines (say 1% of global population) start to look uncomfortably lower than 100%.
1. I don't doubt disruption in global food production will likely cause some famines, but again, plenty of places will still be able to grow food, and in fact many places will open up to food production.
2. I don't see how any increase in communicable disease spread leads to anything close to "we'll all be dead".
Yes, lots of people will die due to the impacts of global warming, but nothing I've seen says there is any reason to think it will be a species ending effect.