New teams start up for a myriad of reasons. Whether they succeed or fail depends on whether there is a demand and if they can deliver what they promised, just like in any business.
At the younger ages, I see teams starting up to challenge themselves with greater competition. You usually don't see many new teams at the older (16U and 18U) age groups. Once these teams start playing travel tournaments, then the girls and parents see other teams and organizations and just what is available to them. Some of these families will move to other organizations/teams that they feel can help them meet the goals/aspirations that a girl might have.
At the younger ages, your team can get into just about any tournament to prove to your families that you can deliver what you promised. If you do not deliver, they will find an organization/team that does. I also have seen some new teams will disappear within a year or 2 because the founder/coach will move to an organization, new or established, so that they can get more resources (money, facilities, tournament opportunities) to help develop the girls.
A new team at 16U or 18U will find that they cannot get invited to Showcases because they have no history to prove their competitiveness. Showcases want very competitive teams. College coaches what to see their prospects playing in a highly competitive environment. Most of these teams will not last long.
The established organizations/teams do not hoard pitchers or other players. The families are free to move to any team that they wish, within sanction rules. Organizational teams have at least 2 quality pitchers per team because they know it will better their chances of playing late into Sunday. These girls know that they could go to any new team and be a #1 pitcher but the know that they will probably not get very deep into elimination play due to the stud pitcher running out of gas after back-to-back games.
So, can Ohio support all of these new teams? The market will determine that. Some will succeed, some will falter and disappear.