Word for someone who likes to define things simply

A word for someone who likes to define things, often to a detrimental effect by over simplifying them - due to either lack of intellect/laziness etc.

I’m thinking of Trump like figures who rather than explain something/someone is complicated , use a single word to describe it.

Example, After being explained why his computer was not working by the IT technician for the 6th time and Jim still unable to understand, Jim called him a nerd. The IT technician replied “you don’t know anything, perhaps you should stop calling people names and being such a …”

Or.. After the meeting with the leading human rights lawyers of the day, Trump unable to understand the intricacies of the debate labelled them “interfering liberals”. A journalist noted this was the first of a series of names Trump used throughout the conversation in order to deflect from his lack of detail, an action increasingly being called … by some in the media.

I hope that makes sense and isn’t too ironic

Solution 1:

reductionist maybe.
Lexico defines it thus:

often derogatory

A person who analyses and describes a complex phenomenon in terms of its simple or fundamental constituents.

‘a crude reductionist’

It's an older word than I imagined: from 1861, according to Etymonline.