Well,
“Does it have a name?” is a question that could use a little contextualization on its own. There tends to always be something normative in questions of definition. (This is a case of an inverse definition, where you want to know not what a word means, but what a thing is called.)
Obviously, you wanted to know specifically in the field of “linguistics”, but the matter is still the same. When someone normatively claims what the definition of a word is - implying there is a right or wrong answer, like that the phenomenon you mentioned is not called “symbology” - they can only do so with a tacit assumption of what examples are worthy to be used as evidence, and what are not. A normative definition is compromised of:
- An empirical observation: who used the term? Did this occur? The ^existence* of the term, at all.
- Is it ‘legitimate’? I could tell you that I read some friends who called it “Big-Casing It”. This is an empirically real (if true) incident of somebody pairing a language object (a series of words) with a thing. Is the answer acceptable, though?
It implies:
On the one hand, there is no end to the number of things you could call it - as a subjective human, you can freely associate what it means to you, what impression it gives, and what word or phrase you think would draw out the aspect you want to stress.
Because asking for the ‘correct’ word for something has no empirical or objective answer than “any word at all, you can make one up”, the only remaining part of the question, as to a ‘correct’ one, is, what do you mean by correct? What is the implied context here; whose word for it do you want to know; or, what would be some of your criteria for distinguishing between the right word association (amongst infinite possible ones) and a wrong one?
Then the question hinges on, what aspects of that are you trying to draw out?
You already provided two words, ‘capitalization’ and ‘emphasis’. Perhaps we need more specification, to define clearly, the context, where we should look in, for a word?
For example:
What do you think the effect is, when you read text like that? In this case, it’s expressing that some people are self-important, haughty or snooty. Why? Why does changing the letters have that effect? Some hypotheses:
- Capitalization in English associates with proper nouns. By drawing that association, does the device imply that it’s a specifically known tendency - a recurrent attitude, that deserves its own name? (Somewhat in the direct of like how “fear of missing out” became “FOMO”?)
- Capitalization often conveys “bigness” - we can emphasize our language BY WRITING IN ALL CAPITALS. Does the choice of letters just serve as an intensifier - does it cause the text to stand out, in any way? Or, does the “bigness” of the letters, connote the “bigness” that the snooty people see themselves as?
I am trying to give you what I think is a real answer to your question - “is there a word for that” - there can be many, when you look far enough. But that’s because it’s open to interpretation, because humans use their intuition in inflecting their use of language, in accordance with the impression it gives them. To find a good word for that, we should pursue further, what you think ‘it’ truly is, more precisely - or else we can just say, “It’s called capitalization.”
When you ask yourself “What is this? What’s really going on here?” the question could easily go beyond the standard confines of “linguistic theory” - the human association of “big letters” and “stuck-up people” depends on an ocean (an ontology) of knowledge - about our culture, about English, about words like “little people”.
In my opinion, you will get the best answer by interpreting it yourself: what do you think it conveys? Your impression is as good as any other, because only a human can say what they feel language really “means”, can attest what inner states it provokes.