LSMs are also useful for coping with (i.e., cleaning up the messes/consolidating no-longer-relevant historic events into just their final state) streaming/windowed multi-temporality as happens from lifting iterative/fixpoint computations from batch semantics to streaming/incremental updates.

You have to consolidate when the time has come to reclaim space and to avoid needless repeat compute during accesses. Might as well use it to run full LSM tactics. Especially when keeping in mind that array mapped trees have very simple index arithmetic once you treat them as semantically literally identical to a sorted (SoA) array with a cache-benefitting address/index scrambler.