Why are JS frameworks not used so often?

Question

JavaScript

Hello.
I am a back-end developer with 3 years of experience. I decided to move to the front-end. There are no particular problems in laying out the site, but I realized that layout is no longer surprising, because for 3 years, client technologies have stepped far forward. I started learning pure Javascript, looking ahead I want to learn some js framework in order to create high-quality projects with an emphasis on performance. I saw Angular and Polymer, looked at examples of sites on them and was impressed. The interface is similar to an application, everything opens quickly due to Ajax requests, everything is smooth and flies in a word, you don’t need to connect a bunch of scripts and so on. Question: why are so few sites in RuNet using these frameworks? Is it time consuming for training/development, therefore unprofitable for companies/business or for other reasons? I think if they were used more often, then we would make our virtual world much better for our users. Forgive me for a possibly stupid primitive question, I hope the front-end workers explain, for which I will be very grateful to you

Answer 1

why so few sites in RuNet use these frameworks?

because they are websites. Because search engines need to index content. Because it's runet. Because 90% of developers are not qualified enough to effectively make Single page Applications. Because 80% of RuNet is made on wordpress/joomla/dle/etc. Well, something like this.
I’ll tell you about search engines and conversion separately. If your site takes a few seconds to load, you will lose conversion. Also, search engines simply do not know how (with reservations) to index dynamic sites.
There is a solution for all this - serverside prerendering. They usually do it either with the help of third-party solutions in the cloud (which is not cheap for an ordinary blogger / online store or stupidly many risks), which are also not always painless to use, and on the server using node.js. Moreover, this approach began to gain popularity in 2013 with the advent of react and the concept of a virtual home (they used it before, the same twitter). Moreover, in the same react it is still not the most trivial task to do everything so that there would be no pain. So far, the leader in terms of painless implementation is Angular2, which is helped by dependency injection and kilometers of abstractions. But only it has not even been released yet (although everyone is already freaking out on beta). Well, again, this will not take off on "shared hosting" (with reservations, again,
Every year the number of SPA increases. Over time, most people will switch to similar approaches. Again, there is common sense. For example, cutting a landing page on all sorts of react or angular or vue is an overhead. Here and vanilla javascript is enough.

Answer 2

You, as a backender, tell me - why do people use self-written guano in php instead of writing in django?

Answer 3

About Polymer:
Not all browsers support the technologies it uses properly. And the point is to write a site that will not be displayed in some browsers.
According to Angular:
I do not need 80% of this framework, and for the sake of 20% it makes no sense to drag it into my project.

Answer 4

Because for most even responsive sites, a clean layout is enough, and JS / JQ is needed mainly for the carousel :)
There are orders in freelancing in which people require a site with 3 fixed-width columns of 5 pages, use bootstrap and bitrix. Here they can put something else in there.

Answer 5

I read the docs on several JS frameworks and then finally decided that I would study the backend). And also bad indexing by search engines.

Answer 6

As already noted, bad indexing. Perhaps this is the main reason.

Answer 7

I'm not a pro, but sometimes small orders slip through, and I often use angular (but within what I can), jquery, as I understand it, is generally a super heavy library, and I hear about polymer for the first time, but I'm more inclined to the backend