This article is a success story for MySQL because maciej is using MySQL.

This article is a failure story for maciej. MySQL may have chosen correctly for its own popularity (although that's debatable; this choice might not be a success factor) but it did not choose correctly for the success of its users, with this article being a clear example.

It's not theoretical. MySQL by default allowed type coercion out-of-box that is nonsensical. Sure, type coercion can be nice, but I'd prefer none over if it not failing and coercing bin('y') to 0.

Attributing their success to their choice of DB is insulting at best.

MySQL chose correctly, not maciej.

The coercing bin('y') to 0 makes no sense though - I agree with you there.

Those two statements conflict with each other and I don't see how you reconcile those without placing blame on MySQL.

Every product has bugs.

The philosophy of attempting to work when possible (coercion and other things) is good.

They clearly messed up here, but it doesn't mean they should never try to coerce values.

Even the warning when you try it makes no sense (what double?):

   1292: Truncated incorrect DOUBLE value: 'y  '

It's clearly a bug, and not something fundamental to MySQL.

Sure, I think we agree. I agree it's a mistake here and should be corrected, I wasn't advocating removing type coercion by any means, nor do I think that this one-off (?) incident is worthy of making broad statements about MySQL.