We could, yes; it would be the cleanest method ever, but not all of us are able to do it and the work could be more complex than expected. Still speaking of WordPress (since it is the most used CMS) we could get around it with a plugin like W3 Total Cache that we have already mentioned previously, but this time trying to select the aspects that interest us most related to CSS and JavaScript (always making sure to have a backup of the previous situation at hand to avoid unwanted disasters).
NB: Before touching on all the other features (it is not a course on the plugin) let's go through here, try to understand if or how much the situation improves and then, if necessary, we go to fix elsewhere. The the benefit of our ios database important thing is to always empty the browser cache and try to navigate with for example Chrome, Firefox and Edge (Ex IE), because it can happen, especially with CMS (not knowing well how the themes are structured), that the changes may benefit perhaps on Chrome or not work at all on the others.
Anyway, how? Once installed, in the WordPress dashboard, just go to Performance > minimize , scroll down and look for the relevant sections.
Check the enable box , save by clearing the cache and try the page speed tools if anything improves.
W3 Total Cache, CSS and JS panels
From the screen we see in the figure on the right the "Operations in areas", in the section dedicated to JavaScript. The default value can be changed depending on the type of script we have on our site and also depending on the indications given to us by the Page Speed Control.
NB: Yes, not everyone is able to choose between the options, but the plugin in this case does not apply definitive solutions and we can still go and change to verify that everything is ok, always trying with empty cache and with multiple browsers.
An important note should be given to the sections below, where you can specify everything that should not be "minified", because due to the structure of the site/blog you have, there could be compatibility problems with what you are going to do.