Translation:The reporters visit the politicians.
Actually, without "meg-" it would sound like a habitual action: the reporters keep visiting the politicians. And thereby it becomes a general statement. But that does not mean that "meglátogatják" is necessarily progressive.
There are ways to express the current action but it is more of a contextual thing in Hungarian. For example, if you want to say that they are there right now on a visit, you can say "a riporterek látogatóban vannak a politikusoknál". Or you can express it indicating the time as in "currently", "today", "at this moment", etc.
I believe this lesson’s grammar Tips suggests that this sentence could be expressed as “A riporterek látogatják meg a politikusokat”. What would be the difference in emphasis and nuance in repositioning meg? Is it always an option to separate the prefix, only under special circumstances, or obligatory under certain conditions?
In the official translation "A riporterek meglátogatják a politikusokat." - the emphasis is neutral or on the visiting (the pre-verb is still attached). Hey, what are those reporters doing? They are visiting the politicians.
“A riporterek látogatják meg a politikusokat”. - The reporters (not the hairdressers) visit the politicians. (Who is visiting the politicians?)
"A riporterek a politikusokat látogatják meg" - The reporters visit the politicians (and not the kindergarten teachers). (Who are the reporters visiting?)