It was definitely open to everybody. The points guy you quoted got 3 himself, including online applications

http://thepointsguy.com/2014/06/getting-my-third-citi-executive-aadvantage-100k-offer/

If you think it was only targeted, tell that to the people who all got multiples on Flyertalk: http://www.flyertalk.com/forum/citi-thankyou-rewards/1511082-citi-executive-aa-mastercard-october-2013-september-2014-a-256.html

Again, it was extremely public:

http://travelsort.com/blog/citi-100k-executive-aadvantage-offer-still-available-plus-expiring-offers

There are no cards in Canada that would allow for multiples to that extent, and if there was, I would definitely not be surprised if there is more Aeroplan inflation as a result.