No obsolescence, just internal hardware that is too old to run more sophistcated software.
Apple fully supported the 2013 iPad Air 1, iPad Mini 2 for a full 6-years.
AND Apple is STILL supporting security updates on these 6 year old devices, to date!
That is why iOS 12 is currently up to iOS 12.5.2. The last full iOS 12 update from Apple was iOS 12.4.4.
Also, still lots of third party apps that support iOS 12, currently, but this will start to dwindle off during this year and into 2022.
So, that iPad has, at least, another year of support from third party app developers.
For your bank software, try using the Website instead of the app using another, more up to date,,third party Web browser.
Look at using Mozilla Firefox or Google Chrome Web browsers OR one that I use that is a favorite of mine and newcomer to Web browsers called ALook Browser.
It’s a fast, fairly easy to use third party Web browser that was designed toward older iPad models, but still works very well with new modern iPads, as well.
For ESPN, you might try the Website, instead, using another more up to date Web browser and see of the Website will allow you to login with your ESPN login credentials.
Most Internet/Web based apps are just portals to the regular Website, anyways.
Best of Luck to You!