I was waiting over 30 seconds to load and it seemed to be stuck on the preloader. I tried again and the next time it was a bit faster, but I am generally wary of preloaders, because they can be hit and miss like that. The big problem is usually if you are calling on external resources where everything can be held back by something really small
My phone is on the large side in terms of physical height, but also quite narrow and I’d definitely expect to see those images stacked vertically in a single column. It shouldn’t be hard to set each column as full width at xs and sm breakpoints in Blocs 3.
For the poster images you have quite a few on the page and I just dragged a couple to my desktop, so I could check the sizes. The laundry appliances image is 319kb and if I run that through https://tinypng.com/ it comes down to 82kb. The Carnation image is almost 400kb and it took 2 seconds reducing that to just 102kb without physically reducing the dimensions. Multiply that kind of saving across the page and the difference is massive.