To my mind, it’s meddling when, as @dolphinboy notes, the owner gets involved in the day-to-day operations of the team, especially decisions about players and coaches. You could have a hypothetical case – like, in the past, when Paul Brown owned the Browns, then the Bengals – that the owner actually knows enough about the sport itself to be a credible GM, but I think that those days are long past in major professional North American sports.
At this point, being a GM in the NFL or other sports leagues is absolutely a full-time job (and then some); any team owner likely has many other business decisions that they need to be focusing on (with the team as well as their other businesses), as well as almost undoubtedly not being experienced in the nuts and bolts of running a team. Good GMs come up through the ranks of scouting, player personnel, operations, etc.
Jones is the poster child for this, because he actually has given himself the GM title. As discussed in another thread here, he seems to be under the impression that the skills he had as a GM in the 1990s, when the Cowboys were winning Super Bowls, are still enough today, when the game, and the administration of an NFL team, was much less complex than it is today. (Also, there’s the matter of how much of Dallas’s on-field success was due to Jimmy Johnson back then.)
I’ll also add George Steinbrenner to the list of examples.
Well, yes, at a certain level. It’s your team, do what you want. But, if you, as a team owner, lack the brains and humility to realize that you need to let actual professionals do their job if you want your baby to be successful on the field / on the court, then you absolutely do earn the “meddler” title, IMO.