It may depend on the journal and field a person is in.
I used to type and edit manuscripts being submitted to science and geological journals for several geological professors and never did I see anyone use a contraction or exclamation point. They also never used 'a lot' or 'lots'... or personal pronouns. They were very careful to be as explicit as possible, and if they did use 'a lot', etc., it would come back from the reviewers X-ed out, with alternate suggestions.
Thanks for addressing this, Mame.
I would say that the standard for all academic fields and journals is pretty much the same. Granted, given that these are merely conventions, ie. not real rules of the English language, different groups/journals, magazines, ... have their own style guides.
There's a difference between one person's anecdotal evidence and that which is revealed in corpus studies.
And you're absolutely right that this particular register, academic prose
, tends to be much more formal. That's understandable and sensible.
The only problem is that this particular person seemed to be just another hard case prescriptivist. We see that in the contradictions found within their lame, academically speaking, advice.
Do not use phrases such as, "a lot," "lots" or "lots of," which can usually be replaced with one of the following words: many, most, much, often.
The contradictions in "Do not" and "which can usually be replaced ..." should make these people blanch with shame.
Do not use exclamation points, for they are almost always unnecessary.
The same here - how is a sensible person to understand this;
Do not use them but use them when they are necessary!
I didn't attempt a Google Scholar search for that nonsense about not starting a sentence with a conjunction because it was impossible to filter out all ands, buts, etc.
There are very good reasons that we don't commonly find the usages contained in these admonitions in academic prose. But to prohibit them outright and totally, which this person does on one hand and allows them in the next breath is idiocy in the extreme.
This is simply another example of a person, an academic no less, that is ignorant of the larger picture of language use, so they resort to these narrow, contrived rules.
Chances are, a review of their own writing would find that they don't follow their own prescriptions.