In a network of just a few computers, are there really that many cached requests? Local DNS caches will already cache short term and TTL of most domains is probably too short to get much caching beyond that.
Looking at my dnsmasq statistics, only 16.3% of 10,776 queries in the last 24 hours have been answered by the cache. Another 21.7% never left the device, since they were in the block lists, but that still leaves 62.0% of queries to be returned by 1.1.1.1 and 1.0.0.1, which is my external DNS provider.
Although this doesn’t count on-client caching, it still seems to back up your guess and my original comment.
Although this doesn’t count on-client caching, it still seems to back up your guess and my original comment.