That's incorrect - at least in the recent past.

Of course, the Europe Business Cabin is not always full, so it will often happen that you don't have anyone else in your row - but this is not because a seat was "blocked", but rather because the seat remained unsold.

Seat "blocking" works as follows:
MIDDLE seats only are blocked. This ensures that no passenger in EBC will have another passenger immediately to their left AND immediately to their right.

In the Fokkers and Embraers that only have 2 seats in a row, this can never happen anyway (as there is no middle seat), so no "blocking" occurs in these rows.