There's been plenty of speculation that Putin is suffering from some illness that has effected his judgment. The Newsline article (link below) doesn't provide proof that Putin is having health problems, but it seems to be a bit better than some of the reports floating around.
If Putin is sick, and if he's being treated with prednisone, he might be mentally unstable (I'm not convinced he is, hence the 2 "ifs" and a "might"). This could go either way, though. Perhaps Russia wants the West to think Putin might unstable so they take his threats seriously, or at least have uncertainty about it. Or, as the article speculates, perhaps the rumors are being circulated to weaken Putin internally. Of course, people could be starting the rumors for some other reason(s).
>>>An oligarch close to the Kremlin was recorded on a tape saying the president is ‘very ill with blood cancer.’ Is this true, idle speculation or disinformation designed to make an erratic and paranoid dictator vulnerable?
. . .
Myeloma, even the more aggressive forms of it, doesn’t necessarily require chemotherapy at all anymore. It can often be treated with immnuno-modulatory agents and steroids . . . Steroids – a common one is prednisone – attack malignant lymphocytes that circulate in the blood, but they are also known for two common side effects.
The first is a high risk of infection owing to how badly they deplete immune cells. “Anyone on heavy doses of steroids will find it much easier to contract COVID-19,” Grossman said, which might account for Putin’s extreme germophobia and recourse to Howard Hughes-like seclusion. Pneumonia, too, can easily kill an immunocompromised steroid user.
And the second side effect?
“
Deeply irrational or paranoid behavior.”<<<
An oligarch close to the Kremlin was recorded on a tape saying the president is ‘very ill with blood cancer.’ Is this true, idle speculation or disinformation designed to make an erratic and paranoid dictator vulnerable?
newlinesmag.com
I do wonder if the article above is overstating the side effects of steroid treatment with regards to behavioral changes. The list of side effects at the Mayo website is longer and somewhat less alarming.
Are you using a corticosteroid? Prednisone and other corticosteroid pills, creams and injections can cause side effects. Find out what to expect.
www.mayoclinic.org
Having said that, even if Putin doesn't have cancer or some other illness, he does seem to be at least halfway off his rocker.