That just sounds like a lack of real world implementation to me. Assuming it works for what the school needs, it can probably be adapted to other systems I would think. Just like if you or I wrote a project, is it not real until someone else implements it?

Banks are notoriously slow on the uptake of tech projects, it might take some internal pushing from people who care to adopt a FOSS solution. Most business I've run into prefer proprietary projects because its easier to just throw money at something, although they could throw money at their internal team to implement FOSS. Unsure if it would be more expensive in this case, I'm not very familiar with fintech