I've seen the hype about bamboo as a climate panacea, and there's a lot wrong with this line of thinking.
First, and this is a quibble, but bamboo is not a tree, it is a grass, in the same family as oats, wheat, rye, and bluegrass. Trees absorb more carbon than a bamboo plant; the bigger the tree, the more carbon it absorbs. Bamboo gets hype because a field of bamboo can absorb more carbon than a forest of trees in the same area of land. Bamboo's carbon absorption stats doesn't come from special biology, but the fact that it grows both tall and tightly packed, while other grasses don't grow as tall, and mature trees aren't tightly packed.
But trees are still extremely effective carbon sinks, and land with trees on it can have multiple uses, while land filled with bamboo is impassable. A large mature tree can absorb enormous amounts of carbon while also decreasing the cooling requirements of homes beneath its shade.
Bamboo has limited use besides being a carbon sink. It is an invasive species, so widespread adoption of bamboo farming outside its natural habitat can decimate biodiversity. In climates with long dry seasons, dried and dead bamboo is a fire hazard. The tightly packed stalks gives fire a continuous path, and the hollow sections explode when heated, spreading the fire even further. When bamboo is burned, its carbon is released back into the atmosphere.
The focus for building biological carbon sinks shouldn't be on min/maxxing short term carbon absorption, but on keeping that carbon from returning to the atmosphere at the end of a crop's lifecycle.
There is no climate panacea, only baskets of solutions.
Bamboo has remarkable properties from an engineering pov - strong light hollow tubes, and so could be used more to substitute for plastics and metals, in relatively short-lived products (which most are). You are right that it's not so durable as wood from trees, and it’s more suited to wet climates. I have several kinds in my garden, green in winter, grape vines dangle along it in summer, a shallow root barrier (old tiles) contain it.