Why should I follow google seo and speed rules?

I would like to know why should we follow google rules ? as I see google don’t do what they tell us to do.

I have 2 companies and each company has their own websites (Domains) one of them is almost 100% seo optimized and 96% – 98% performance https://www.tedigrup.com/ second one is using wordpress and not seo optimized even doesn’t have much contents and mobile usibility is very low 10% – 20% and same score for seo.

But the one not seo optimized is ranked on the top of the search result in google, with same keywords and same descriptions, even with less descriptions and contents.

Google says they don’t use keywords https://support.google.com/webmasters/answer/79812?hl=en but they do.

There are lots of websites well ranked by google which is not seo optimized.

Difference between two of my domains, second one is taking lots of backlinks from forums and other sites.

I think that is why its ranked by google.

if so! then we don’t need a seo optimization, we can add our site links to toplists (directories) and join forums and discuss about it in a few forums or comminities and get ranked on the top of the search engines.

Second thing about title and h1 most of people says they should be the same, but what I see in top ranked sites is different. For example my top ranked site title is like so :

<title>Why should I follow google rules? domain.com</title>

h2 is like so: <h2>Why should I follow google rules? </h2> without Brand.

I don’t have a h1 tag in the top ranked pages but have 1 – h2 in each page.

And well meaned in content about words in title tag, that means google doesnt care about h1 tag (They says they do which is a lie).

So, I think google ranking natural pages more than seo optimized pages.

What I see, They care about title and content in page, so we need to well mean in content about words in title and get backlinks to get ranked by google.

So, Can you guys tell me why should we spend hours and days on seo optimization ?

I am not english so I might have some speling mistakes.