The IRS cannot spend money on things it's not budgeted for. Did you know the IRS returns $7 in additional taxes for every $1 in fraud prevention funding it gets at the moment?
Literally, a 700% return on investment, yet when was the last time any budget passed by congress raised funding the IRS to hire more auditors?
EDIT: Or let's take the articles conclusion: yes, obviously the government agencies should do better. So naturally we can conclude that the Republicans championing this investigation will be pushing through legislation mandating and funding appropriate upgrades - after all it seems like the inquiry has revealed serious issues which require some dedicated staffing and finance to sort out for a very important agency of the government.
Of course obviously that actually means this will never happen.