It doesn’t appear that the slow loading time of the linked page is due to Shopify. Taking a quick look at your site in Chrome Dev Tools, your linked page is transferring 13MB of data over the network during page load. Of that, about 9.5MB is due to the 5 .gif images on the page (see below screenshot), and all images account for 10.7MB.
There are three quick changes you can make that should significantly speed up the page load time:
1. Use .mp4 files instead of .gif
For the same quality, mp4 video files will be much smaller than gif. You can read more about this here: https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/replace-animated-gifs-with-video/
2. Lazy load images
Lazy loading refers to loading images only when the user scrolls, or once the first part of the page is already rendered. In your case, it looks like your theme is equipped with the lazySizes lazy load library, but is not making use of it.
The troublesome gifs have a class of “gf_image”. In your theme code, try adding the “lazyload” class to these elements like so:
class="gf_image lazyload"
The lazySizes library/script should then lazy load those images, helping to speed up page load significantly. Note: lazy loading also works for the mp4 files you should use (from above).
3. Compress large images
You can use a tool like https://squoosh.app/ to significantly reduce image file sizes, with barely any reduction in image quality. At the default quality setting of 75, this tool reduces the main product image from 85.5kB to 63.4kB – a 28% saving.
I recommend testing your site with Google’s Lighthouse-based tool: https://web.dev/measure It provides actionable suggestions and provides links to extra resources for further reading. There are a number of other optimisations that can be implemented, but these 3 should be easy to implemented and provide the biggest wins.
I hope that helps 
Troublesome gifs:
