The short answer is ¯\_(ツ)_/¯

There are too many unknowns. First we do not have a very solid idea of how life starts (AFAIK). We believe it requires large amounts of UV radiation (which the early Sun emitted). This also happens with young M-dwarfs. Then, once you have RNA chains, you need low radiation to not destroy it. That happens with old M-dwarfs. The difference is mostly the timescales. M-dwarfs spent much longer in the "active phase" and get later to a quiet phase. This star in particular is very quiet. Maybe life just happens later (this last part would be me speculating).

The long phase of high activity can strip the planet from its atmosphere, but when thinking about life we mostly consider secondary atmospheres. These are atmospheres that didn't form with the planet, but that arrived later after the loss of the primary atmosphere (Earth's atmosphere is a secondary atmosphere). If the planet could form an atmosphere after the star entered its quiet phase, then it should be fine.

This will also be affected by whether or not the planet has a sufficiently strong magnetic field, which currently we can't measure. In Earth, the magnetic field is created by the convective motion of the liquid outer core, which is then amplified by Earth's rotation. If the planets are tidally locked you would lose that amplifier, because of the slow rotation, but you would gain another in the form of tidal forces. So... it's really difficult to say. AFAIK there are models predicting many different outcomes and, as we know very little about possible core configurations, it is very difficult to decide which ones are more realistic.

Then what happens to the temperature if they are tidally locked? Well, it depends a lot on the atmospheric circulation. It has been traditionally expected to have a very hot and a very cold side, but once again now you have models predicting wildly different things based on different conditions. If you manage to get fast atmospheric circulation (which can exists based on convective currents and tidal forces), you can reduce the temperature of the hot side and increase the temperature on the cold side. Currently very difficult to conform or deny anything.

So I guess the long answer is ¯\_(ツ)_/¯ but with more words.

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Honestly, we are still far away from properly establishing habitability in any exoplanet. We can probably reject it in some, but I would say we don't understand life well enough to even do it systematically.