It's so ridiculous mining on a phone. This can definitely shorten the life of phones. Google has taken such steps thinking about its own users. So this decision is absolutely correct.
it is ridiculous to some,to some it is an extra little cent,standards of life are different in different countries
it is not profitable by any means and in most cases-silly to mine on your phone
but to many this could be a way to learn about cryptocurrencies
you think Google is absolutely correct,I don't think it is absolutely correct to simply ban ALL cryptocurrency related adds and aps
mind you it is not only miners we are talking about here,it is a much wider array of apps