Within the realm of the range of batteries, charging devices (alternator), and load we are talking, nothing in that article would apply (that the alternator can’t adequately charge the battery, the fuse panel can’t handle it, etc.). It is very poorly reasoned. Car manufacturers will use the same alternator and regulator package for a variety of installed batteries, for example. Specific cars will even dictate different batteries are acceptable. One single example, I have a Volvo with the battery compartment specifically constructed to take different batteries from 750 to 1000 CA - all just fine to use with the same alternator, regulator, fuse panel, per the manual.
As a second take, that article is terribly vague, unreferenced, and authored by someone without any evidence of experience, credentials, or authority. I know you are repeating something you’ve heard in good faith. My point is not to inherently contradict you, but to point out that there is just a tremendous amount of wrong advice given out by mechanics, and especially by on-line PAID writers on automotive subjects who don’t have the training to do so. Selling revenue clicks is far more important than getting quality advice for most web sites.