Your "Golang is giving high latency for firestore reads writes"
posting in GitHub, provides 2 code samples that are meant to be equivalent, the one written in Go, the other in NodeJS. They need to do the same thing, for the sake of latency values comparison. It appears, though, that these 2 samples are not equivalent, as the NodeJS one contains an extra "where" clause, namely: "where('phoneNumber', '==', '
+919113348990')". If this is the case, they won't run the same way, as less data is expected to be retrieved by the query in NodeJS with the "where" clause. This being so, latency is expected to be smaller too.
You may test if the retrieved data volume is at the root of the issue by using a "limit" clause. An example of a data read operation is given in the "Read data"
sub-chapter of the "Get started with Cloud Firestore" page.