Yes, much more severe. Covid alone had a higher fatality rate than Spanish flu. 2012 MERS had a 30% fatality rate. Ebola strains in Zaire and Sudan have had fatality rates over 50%.

Nope, much less severe. COVID-19 had an infection fatality rate way lower than 1%.

https://doi.org/10.1016/j.envres.2022.114655

As for those other diseases there is zero evidence that climate change has made them more severe. It's not impossible but we simply have no reliable evidence of a causal relationship one way or the other.

You can't cherry pick a single century-old example and use that to prove the opposite. That's not how logic and reasoning work.

You can't claim that global warming is making diseases more severe without hard evidence. That's not how logic and reasoning work.