Can you clarify what you mean by underpowered? Not every site wants to replace terabytes of disk with NVMe storage to make paging faster - especially sites that have a lot of throughput and long retention demands.
Second, even if quotas could be used - and there are plenty of sites where they cannot - there’s still a broker-replacement scenario that needs to be accounted for. Most folks don’t want to intentionally impede the recovery rate of a failed broker.
That's unlikely unless 1) your hosts are seriously underpowered and 2) you have no per-consumer quotas set