That's true but not particularly relevant to database performance. As I mentioned, random reads on an SSD do not suffer from a head seek penalty so it doesn't matter how the blocks are allocated. On the other hand with spinning disk there is a huge difference in throughput for large sequential vs small random reads.

What about TRIM?

TRIM is like the free() equivalent to malloc(). It releases a NAND page back to free state for other uses. It dones't require any NAND access or writes per-se but if persistent TRIM is needed (vs best effort,) it gets much more complicated.