Unless you want to use Nginx as an SSL-offloading proxy for a bunch of internal apps that you want to protect from the public but your apps themselves don't use the session in any way? Yes, we can use Lua and effectively write our own, but one of the reasons I've considered Apache again is that there's now a plugin for OAuth 2 + OpenID Connect ;-) https://github.com/pingidentity/mod_auth_openidc
You'll lose some of the benefits of Nginx at that point, since part of why people like Nginx is how it handles connections, proxying and caching. And the internal apps aren't always mine to maintain, e.g. Apple's Xcode server.
But yeah, there are options in Apache-land, my post was more that nginx could eventually gain those options too :)
That said, even before this, Apache supported a million different mod_auth_* at http://httpd.apache.org/docs/2.4/mod/ including authentication caching http://httpd.apache.org/docs/2.4/mod/mod_authn_socache.html for modules that don't supply their own cache.