The thing is, it requires so much for a planet to last long enough for that to even happen.
Our own planet is lucky. We live in what is called the "Goldilocks Zone", so we have what is believed to be the optimal conditions for life to originate in and flourish. And even with that, life multiple times has damned near been wiped out, from life itself on at least two occasions, to impact events. Not to mention what a planet would get in a more active part of their galaxy like random radiation blasts, something we thankfully avoid by being in a quiet little backwater of the Orion Arm. We really are in a remote part of our own galaxy.
And even more important, due to a fluke of early development of the solar system, we got a "Super-Sized" core. Where as our nearest cousins of Mars and Venus have either a dead core or one only kept alive by tidal stress because it is so close to the sun, ours is still active and protecting our atmosphere and life with radiation belts that deflect most of what the sun emits that would be fatal to life. We were lucky, because when Theia hit us some 4.5 gya, it blasted off the crust to form our moon, but their core merged with our own to form a super core that is still highly active to this day, and will remain so even when the sun goes Red Giant and consumed our planet. The core will literally live longer than the planet would.
And this is what I base my belief on that the majority of life never developed much past "pond scum", as most would likely go the way of Mars (which I do believe once had life). The smaller core cools, the radiation belts diminish, and increased radiation along with the solar winds removing the atmosphere put an end to life on the surface. However, as I also stated I do believe that life still exists on Mars. But in the form of extremophiles, only existing underground in their own little ecosystems. Condemned to never evolve much past what they were like when they became trapped, closed ecosystems which remain small in numbers, utilizing what little geologic forces are still present in addition to their own life-death cycles to barely remain in existence.
And in the last half century or so, we have only started to scratch the surface of extremophiles on our own planet. And they exist in environments that at one time was thought to be impossible for life. However, we also know that they almost never evolve past what they were when they entered that environment. And if anything, "devolve" to remove traits that are not beneficial in the little area they live in.
