It is rarely used in ranked games. Even if some decks in Duel Links require having a good starting hand to set it's tempo, "Switcheroo" has the upper-hand which gives you an option to retain cards and reshuffle an unwanted card for a specific scenario. In general, using this skill is unreliable, but might work just fine.
I guess that he wrote that before Balance was changed (after reading this page, I would go for Balance over Restart most of the games). However, I wouldn't go as far as to say Switcheroo is better than Restart, not in a million years.
EVERYONE can learn Restart.
It's one of the default 'generic' skills that any character can obtain, given enough luck in grinding, I believe.