[qup]

If you don't have a developer, you need WordPress or an alternative.

The description isn't enough to know if it's something wordpress could handle out of the box.

There are places that host and manage WordPress. If you don't install any plugins, WP is secure enough.

The difference in a Django hello world and a fresh WordPress install is like a million lines of code.

[amts]

It may be a typical informational website for a small agency with up to 3-4 tabs, presenting their services, a blog, some contact form. It may not need much animation or interactivity in the beginning. But optimization for mobile may be useful. I've watched a dozen of tutorials on Django/Flask on Pluralsight/FreeCodeCamp building some simple registration sites, even a basic e-shop. For my former Wordpress site I have several plugins, including SEO optimization. But you mean to not install even the Wordpress recommended plugins?

[xet7]

I did read from somewhere, that with Wordpress SEO plugins etc some website got to top of search results.

Those that did website with other tech did not get same results, and thinked how to compete or survive.

For security, I use Sandstorm https://sandstorm.io fork of WordPress that generates static websites. But that does not work with some interactive plugins.

[PrimeMcFly]

I doubt those SEO plugins make any difference at all.