Yes! It's more than possible. The above is a demo of an aMiSTACX G5 using the following:
AWS EC2 T3-Large
Magento 2.4.1 OSE w/ LUMA theme and sample data
S3 Titanium using S3Rocket, Ramjet, and B24 for Search
Note: No other code modifications! No caching engine except Ramjet. Scores for Google LS will range for Mobile as 80~88, and Desktop 100. With some small tweaks for Mobile, you can reach close to 100.
You can test the results yourself with a turnkey version found on AWS or play with the demo. This same stack has been tested to easily handle 2000 unique visitors per day <20% utilization, and with catalogs exceeding 1 million SKUs.
So yeah, Magento 2 can be a Shopify killa when deployed correctly.
Re: Is it possible to achieve a 90+ site speed with Magento 2?
I originally was very skeptical of getting a high score on Google. I had been using Nexcess hosting for a few years on their "Small" Magento plan. My Google scores were ~32 for Mobile and ~67 for Desktop.
Then I switched to Cloudways. I won't share my site for privacy issues, but I will share the technology used to achieve Google score of 79 Mobile and 99 Desktop. It's also worthwhile to note that Google Page Speed supports HTTP/2 since March 2021. Since this update, all sites supporting HTTP/2 should see a slight bump in score. Reference this document -
As I mentioned earlier, I use Cloudways in the United States. It is a 4-core server with 8GB RAM and 160GB SSD in the Linode data center. The monthly cost is $90. Cloudways uses a LAMP stack with Varnish for caching. Additionally, I have Cloudflare as my WAF (Web Application Firewall) and CDN (Content Delivery Network). The cost of Cloudflare varies based on features you select, but I pay somewhere around $25 per month.
Now, I'm very mindful of the 3rd party extensions installed. I try to use extensions from only one company to keep the conflicts at a minimum. I currently use JetTheme created by Amasty. I originally was using WeltPixel Pearl Theme and a bunch of themes from themeforest, but had a lot of conflicts with the Amasty extensions I had installed. When Amasty released their JetTheme, I installed it immediately. It's not as pretty as WeltPixel, but it's super lightweight without a lot of bloat and built to be compatible with their extensions out of the box.
I'm not being paid or endorsing any of the companies I mentioned above. The great thing about Magento is the number of options available for hosting, customization, etc. But at the same time, that creates a mind-numbing number of choices.