Take, for example, this [performance report of the main ikiwiki site](https://gtmetrix.com/reports/ikiwiki.info/rwUIfK6d). For a very minimal site, it is still making 8 requests and taking ~700ms to load. That's quite fast, but it could probably be cut down to 400ms if CSS and JS were aggregated. If you look at [my homepage](https://gtmetrix.com/reports/anarc.at/uAkMmZaT) the results are worse, because I have larger JS and CSS files: the impact is therefore much bigger and we're looking at 2000ms load times. (Obviously, part of the problem here is the slowness of the uplink here, but one could argue the same problem would occur for downstream users that have a slower connexion.)
One of the recommendations "YSlow" is giving is "Make fewer HTTP requests":
Take, for example, this [performance report of the main ikiwiki site](https://gtmetrix.com/reports/ikiwiki.info/rwUIfK6d). For a very minimal site, it is still making 8 requests and taking ~700ms to load. That's quite fast, but it could probably be cut down to 400ms if CSS and JS were aggregated. If you look at [my homepage](https://gtmetrix.com/reports/anarc.at/uAkMmZaT) the results are worse, because I have larger JS and CSS files: the impact is therefore much bigger and we're looking at 2000ms load times. (Obviously, part of the problem here is the slowness of the uplink here, but one could argue the same problem would occur for downstream users that have a slower connexion.)
One of the recommendations "YSlow" is giving is "Make fewer HTTP requests":