Are planets in a red dwarf's habitable zone actually life-bearing?

http://www.astronomy.com/news/2014/1...ances-for-life

They mention in the above article that as red M dwarfs are forming
during birth, they may be much brighter and hotter than they are during
most of the rest of their lives. And they'll stay hot for hundreds of
millions of years after birth, which is enough time for them to burn
away the water and atmospheres of any planets close to them. So planets
which are thought to be in the habitable zones of these M dwarfs, may
have already been singed into dryness by the time the star settles down
and the planet looks to be in a life-bearable orbit.

Also they mentioned that any water on these planets will have been
stripped into its component oxygen and hydrogen. The hydrogen will have
escaped into space, leaving behind a whole lot of oxygen. This oxygen
then might be misinterpreted by us back home to mean that there is life
processes on that planet, when in actual fact the oxygen is simply from
water being stripped by the radiation of the star. So oxygen may not be
a good indicator of life, after all.

Interesting hypotheses here, to be sure. So perhaps life only starts
naturally around orange and yellow stars like our Sun, and then perhaps
life migrates to these planets (with a bit of terraforming) around red M
dwarfs, when these orange and yellow stars finally die?

Yousuf Khan