[jkingsbery]

The examples in the first paragraph, while not grammatically passive, are functionally passive. They would be stronger in most cases if the author wrote them with the actor as the subject. For example, yes "the bus blew up" is active, but does not answer who acted on the bus.

Being so pedantic, and then saying "but I'm not going to use the technical term voice" is particularly off-putting. If this is an article about grammatical pedentry, let's go all the way. Otherwise, the author should focus on providing useful advice.

[Sharlin]

The phrasal verb "blow up" can be either transitive or intransitive.

"The bus blew up" is a perfectly active clause. "The bus" is the subject, it did its own blowing-up.

"The bus was blown up" is a passive clause. "The bus" is the object, some unnamed entity acted on the bus.

[wrqvrwvq]

For completeness, the transitive active might be "The terrorist blew up the bus". In the intransitive case you can infer the reflexive case (agent acting upon itself), "The bus blew itself up". Some languages have a formal "middle voice" for reflexion.

English lacks a formal middle and there is a good deal of established literature on verbal aspects where the subject is not really the agent called "ergative".

There is utility in comparing "the bus exploded", perhaps unclear as to the agent, but language is not an agent game. It's trying to convey information, which is clear enough in these cases.

[direwolf20]

grammatically active, functionally passive, exactly as GP said

[helicalspiral]

the article is literally going through the technical definition of passive voice

[arduanika]

Sure, but he is packaging it in this superior snark. He is aggressively dismissing the very real thing that people actually mean when they say "avoid passive voice". A technical explainer on its own would be fine, but at least to my ears, this piece reads as narrow-minded and bitter.