Earlier quoted context omitted.
In some ways the app is easy. Capturing what happens is not, especially if there's no immediate incentive to do so. And writing an app in 2020 doesn't tell you want happened in 1660. Then you have to cope with app longevity; most apps deployed in 2020 will be dead by 2030 while the Houses of Parliament will still be there (unless they burn down due to ongoing fire code issues)
Hence having "system/website/app". The system is there to conserve everything and hopefully it will transcend technologies and be easy to migrate the data to whatever comes next.
Digitizing everything helps, but the enemy is still volume, time, and money, and digitizing costs even more money.