Reduce mobile website load time

[Shop Suey]

I/O performance is most important.

You don't need to care about those CSS files.
JS is much worse but if you didn't add any additional JS it is as it is unfortunately.

The slides are too large. That's why your site is 1MB.
You could exchange social icons with font icons.

-> use dedicated hosting
-> optimize the three slides
-> exchange icons

Dedicated hosting will increase the processing performance significantly.
Optimizing the slides will reduce bandwith limitations for mobile users with 4G (or slower) significantly.
The icons are just on top. Part of a clean setup.

If you like you can compare it with my shop.

Mine: Dulles -> Berlin (4.100 mi) on iPhone 14 Pro / 4G -> https://www.roller-aus-blech.de -> TTFB: 1.6s / Speed Index 4.4s
Mine: Dulles -> Kasnas City (1.100 mi) on iPhone 14 Pro / 4G -> https://www.usconverters.com/ -> TTFB: 3.1s / Speed Index 4.7s

Are you using Google Ads? If not then remove gtag code.
Though it is processed in the background it still creates heavy load.
If you have limited server performance the it will affect general performance.
If you nee it it as it is.
If you don't need it remove it. Simple as is.

Send me a PN if you like to have some detailed insights.