Our most recent speed tests for Magento 2.3.6 show significantly better performance running on NGINX + Varnish + Redis + Memcached environment compared to the common Apache - Magento built in cache.  We tested the home page and category page.  Magento files and databases are identical in both environments.  Results are visible below.  On the left column is Magento 2.3.6 running on Apache and built in cache and on the right column is the Magento 2.3.6 running on NGINX + Varnish + Redis + Memcached

Magento 2.3.6 Running on Apache and built in Cache Magento 2.3.6 Running on NGINX + Varnish + Redis + Memcached
Google speed test 1 Google speed test 2
Google speed test 1 Google speed test 2
Google speed test 1 Google speed test 2
Google speed test 1 Google speed test 2

 

Here are some older tests we have done.  The first three columns of tests are done using Magento 2.3.2 + Codazon Fastest - Ellyana theme - Most features disabled.  The fourth column is done on Magento 2.3.2 _ Luma theme.  The tests were aimed to show if Magento is faster on NGINX + Varnish + Redis configuration.  The results are mixed - you can see the table below.

 

  Apache + Magento Cache Apache + Magento Cache + Cloudflare NGINX + Varnish + Redis NGINX + Varnish + Redis + Luma Theme
         
Pingdom.com 1.95 1.46 2.1  1.22
Pingdom.com 2nd run 1.77 1.46 1.34  1.20
Pingdom.com 3rd run 1.48 1.46 1.39  1.20
Pingdom.com category page 3.96 2.96 2.31  1.44
Pingdom.com category page 2.51 2.96 2.42  1.43
giftofspeed.com 3.46 3.66 7.3  
giftofspeed.com 3.43 3.65 3.5  
giftofspeed.com category page 8.17 7.45 5.59  
giftofspeed.com category page 7.52 5.28 5.04  
GT Matrix 1st run 17.1 10.1 10.6  
GT Matrix 2nd run 12.5 7.2 8.9  
GT Matrix 3rd run 9.6 10.9 9.6  
GT Matrix 4th run 9.6 8.4 7.8  
GT Matrix category page 12.6   8.9  
Webpagetest.org 5.05 5.34 5.02  
webpagetest.org 5.06 4.7 5.11  
thinkwithgoogle.com 4.2   4.6  
LightHouse (chrome plugin) 5.4 5.5 5.4  
LightHouse 6.3 5.8 6.1  

 

It looks like in some cases NGINX + Varnish + Redis configuration is actually faster.  However, the Magento Theme  Codazon Fastest - Ellyana theme is not so fast as the name would suggest.  We installed the same configuration on a local server running an old Pentium i5, 8 GB ram running on Ubuntu and Magento was much faster than any hosting / cloud hosting provider we had tried before that.

Our recommendation is to go for at least 2 cpu - 4 GB RAM. and Use Ubuntu + NGINX + Varnish + Redis