Learn Italian: Questi funzionari diventano sempre più pignoli. - These officials are becoming increasingly fussy.

Since this lesson is about emphatic exclamations, how would I rewrite this sentence to exclaim 'How fussy these officials are becoming!' using the pleonastic che?

You could say Che pignoli che diventano questi funzionari! The first che translates to 'how', while the second che is the pleonastic (grammatically unnecessary) one that native speakers frequently add in spoken Italian to reinforce the emotion of the exclamation.

Why is 'increasingly' translated as sempre più instead of a single adverb?

Italian doesn't have a common, single-word equivalent for 'increasingly'. Instead, it uses the phrase sempre più (literally 'always more') to express 'more and more' or an increasing trend over time. For a decreasing trend, you would use sempre meno.

Does pignoli carry a negative connotation here?

Yes, pignolo generally has a negative feel. It describes someone who is 'fussy', 'nitpicky', or 'pedantic', focusing excessively on minor rules or details—which fits perfectly when complaining about bureaucratic funzionari (officials).

The English translation says 'are becoming'. Why does the Italian use the simple present diventano instead of stanno diventando?