ETag and caching

Hello!

I have a question about ETag usage. I make a curl request like this:

curl -H 'Authorization: Bearer <My token>' https://api.airtable.com/v0/<my_app>/<some_table>

HTTP1.1 200 OK

...
etag: W/"10f-SnXCiqHll2qv5oY0Q+Gx4C8/htI"
...

Then I make another curl request like this:
curl -H 'Authorization: Bearer <My token>' -H 'If-None-Match: W/"10f-SnXCiqHll2qv5oY0Q+Gx4C8/htI"' https://api.airtable.com/v0/<my_app>/<some_table>

HTTP1.1 200 OK
...
etag: W/"10f-SnXCiqHll2qv5oY0Q+Gx4C8/htI"
...

Execution time of these two requests is almost the same.

I expect getting 304 Not Modified and smaller execution time.

Are my expectations correct and if they are, what am I doing wrong?

Any help would be appreciated!