First of all, the link you posted refers to B/W Doubles, which was last gen's doubles.
Second of all, the Pokemon listed there are the most viable Pokemon that were used in last gen's doubles, just to recommend the best possible Pokemon to people who are getting into the metagame .
In double battles, every Pokemon is allowed, bar legendary Pokemon exceeding a base stat of 600 (with exceptions of Kyurem and Kyurem-B), meaning all Deoxys forms are viable in doubles.
As you have already mentioned, the only listed sets on that outdated page are of the Pokemon who were of most use last gen.