Make it a choice to only upload original size photos

When I check the /uploads folder of webshops, it has heaps of unneeded smaller photos which really clogs up server space, when I try to move it to offline, it takes more time where as I on my fast internet only need the biggest versions really. Maybe individually, one could tick ‘generate smaller versions’, but I think the relevance is no longer here. Having to code it on functions.php, in a time of ‘let a wizard/UI’ do it doesn’t really seem user-friendly. And getting a featured image is bothersome, it is stored on a separate database posts_meta instead of as an attribute of posts. This would be possible with single URL photos instead of multiple sizes, stored as an array, generated by different plugins. What a mess. I have to reply: “sorry cannot fix your website because the core code doesn’t support it”, that is unprofessional is it.. What if i had a business. I am only trying it out as a hobby right now.
No workable URL, wordpress.com subdomains [probably a commercial multisite offerer for non-code-savvy people] cannot even use custom themes, to showcase it.