Honestly; Teams hold tryouts (especially in your top tier organizations) every weekend they go out to play. (Some even attend HS games looking for that next best thing especially your showcase teams with a blended age group that does not play for a specific national (and there are more and more of these teams forming).
The product a team puts on the on the field, how the ladies are coached, how the coach communicates with TDs, word of mouth from players and players, events "invited too" played in etc. all come in to play as parents look for the next option for their DD that nowadays, "has no start or, end date" as long as they are playing.
The explosion of the non sanction mega tournaments and large organizations has changed the landscape of the game over the past 20 years.
The feeder teams connected to larger organizations (organizations with 2 or more teams at each age group) give them an recruiting advantage especially; with the decline in sanctioning bodies oversite and new sanctioning bodies the past 20 years.
Add in the over all decline in sport participation from recreational to high school everyone is scrambling to keep a float or competitive.
I am also seeing a lot more open events EX: HS age or blended younger age groups that use to only happen in fall ball but now its during summer events. Its hard to have proper sanctioning if 14-18 teams are playing in the same event. These events generally have day rostering or weekend rostering as well some open roster especially at the Adult 18+-23U and I am OK with this at the adult level.
USSSA did a good job for a long time and, IMO has the best website and player/team tracking system but it is not used to its full benefit to maintain player and team eligibility. I remember a time when USSSA had A/B/C tournaments and teams played in their classification and bodies would freeze a roster but USSSA also ran a ton of events and leagues back then.
Now, mainly due to needing to fill tournaments it appears most USSSA events are blended classifications with just a few exceptions.
USSSA may be able to look at what they already have to make changes but I am not 100% sure that the softball community as a whole wants more oversite especially with the price to play today and teams not playing for any specific national.
ASA/USA at one time would issue player wallet cards with insurance info on the back and sanctioning information that included a photo however, with the trend of teams wanting to play "non sanctioned events", players jumping from team to team and families not really interested in sanctioned nationals due to cost many sanctioning bodies now just use a day roster, weekend roster turned in the opening day of the event and hope the teams have insurance on all the players. Back in the late 90s early 2000s Patty and Don did a very good in SW Ohio with rosters and eligibility. USA softball needs to rebrand in 2024 if they want to get back into a lead role with the top tier organizations and teams but like others have stated, that ship may have already sailed.
The sport has changed a lot over the past 20 years, families have changed, economy has changed, player / parent goals and expectations have changed and yes, recruiting and tryouts have evolved to what we have today. I don't see it changing anytime soon.