The answer really depends on a few key things:
- The amount of traffic of your site
- The IT budget for your support
- The complexity of the site and the resources required to optimize
If you have a website that gets a few hits a day, then who cares about 20 queries.
On the flip side, if you are Amazon then you are going to offer the needed content at a large infrastructure cost.
Just about everyone else in the world is somewhere between those two extremes and has to balance based on their own resources.
The only other thing I'll say is caching is your friend.
