Mostly agree with you but some context is required

Cluster bombs historically have a 30% failure rate. The modern American ones have ~1%.

Historically they were used indiscriminately against unknown targets in a large area (they’re really good at that), in Ukraine the Ukrainians are using them against known targets and are logging their use so after the war the area can be cleaned of any duds.

This also isn’t introducing a new weapon to the war; the Ukrainians and Russians have been using their own stocks of cluster bombs from the start, the Ukrainians are just asking for a resupply of the better American ones.