I wonder why domestic and European soccer teams never adopted this trend of attaching monikers to their established names.
Manchester Red Devils
Brighton & Hove Seagulls
It must be really difficult for a team simply named Everton to attract youngsters without a suffix that you can market and use as the basis for a mascot. Except it's not, because sporting culture follows different, more meaningful pathways through family lineage, TV exposure, and success on the field.
In other words, I think these nicknames were simply vandalism of the clubs by the clubs themselves. I would argue they have had no noticeable benefits whatsoever on the success, or popularity of any club that decided to adopt one.
Football has many ills, and faults, but not one club of fans would have stood by and watched their team name be altered in any way, shape, or form. The Hull City Tigers saga was concrete proof of that. Even naming-rights of stadiums are vehemently defended, because this stuff matters*.
*in a sporting sense, not in the grand scheme of things, obviously.