In my opinion, this doesn’t solve the issue many countries have, losing taxes income because the companies choose to pay taxes on another country.
If many countries, such as France, have that 21% of taxes to big companies, and still many others such as Ireland keep their taxes lower (despite raising them up to that minimum of 15%), big companies will keep billing and paying their taxes on Ireland, and the other remaining countries of the EU won’t see any income from the economical activity of this companies on their countries.
From my point of view, the only fair solution to this issues (at least in Europe) is make the companies pay the taxes on the country they generate the profit, the sells. If a customer of an online service, or an online purchase, is located in Spain, the company (Amazon, Apple, Microsoft) should pay the tax on that country rather than paying them to Ireland.