It's not just a matter of the grid, it's also a matter of the rule that is carried out on that grid.
It looks like this is a 4+ state rule, meaning the rule space is massive. To brute force this you would need to not only brute force your way to that small configuration of cells, but you would need to do it for a huge number of different rules before settling on one (I can't say what percentage of this state space would support small gliders, but my intuition says it's relatively rare).
I think maybe you are looking at this from the perspective of studying the game of life, where the rule is already chosen.
It looks like this is a 4+ state rule, meaning the rule space is massive. To brute force this you would need to not only brute force your way to that small configuration of cells, but you would need to do it for a huge number of different rules before settling on one (I can't say what percentage of this state space would support small gliders, but my intuition says it's relatively rare).
I think maybe you are looking at this from the perspective of studying the game of life, where the rule is already chosen.