In regard to chemical weapons, they are decreasing danger because they are not effective in modern warfare. I'd expect for their usage to decrease. Nuclear is is not something proliferating besides North Korea and even then it is deturance and not an appocaliptic scenario. Space weapons are forbidden by treaty and though some countries are playing close to the read line, I doubt that they will be deployed. They would be political liability while being rather vulnerable in space. Hence hypersonic weapons which work better for the same goals.
Iran is the exception that confirms the rule. They were so heavily sanctioned that it became feasible for them to say "screw it, we will do nukes anyway". I won't say that nuclear proliferation is completely stopped, but the system works for the most part. China and Russia are old nuclear powers and them having nukes is expected.
Better counter examples are India and Pakistan, but I don't know the history of their nuclear programs well enough to comment with confidence.
The chemical weapons in Syria were old stockpiles and I'd argue that the use there was not an increase of their use, but an opportunity attack. I don't think that there are many groups who currently have any kind of chemical program and can use it systematically.
