* Only verified number with real losses dead higher and even more crippled.
But the reasons wars existed didn't go away, so this just resulted in more and more people getting killed in "special military operations" or similar things. See e.g. "Why States No Longer Declare War"[0].
[0] https://www.researchgate.net/publication/228896825_Why_State...
Not declaring war provides a workaround, allowing the states to do whatever they desire, without constraints, while avoiding being accused that they do not observe their obligations assumed internationally.
Seems plausible.
In fact, after Vietnam war congress specifically created a law to restrict hostilities without congress approval to up to 60 days, which is what the current (and prior) administrations are acting on.