The issue with your original comment is that it’s simplified on many levels beyond what is acceptable. China has companies working on delivering highest financial output regardless of other citizens and their rights to have fair share in produced goods. They are by no means controlled by workers (why would they accept e. g. 996?) nor creating fair rules to others economically (e.g. Taobao and their alghorims pushing many sellers to sell bellow profitable levels just to maintain visibility on their site). Put it also into wider perspective: China started to move forward in quality of life only after Deng. US system is by no means bad but it doesn’t make Chinese one perfect.

You don’t even realise how strong capitalism is in China.

Polish C is also described as /t͡s/ (e.g. co /t͡sɔ/). According to wiki both are dental and voiceless although one is plosive and the other affricate. As I’ve read their descriptions on wiki, they made a lot of sense - /t͡s/ starts with a blockade of airway (just as /t/) but the air is released slightly differently thus making the difference in sound produced.

Looks weired but a sound of C and T has to be somehow connected, at least it feels like they are to me. Based on my experience, sound of Polish Ć and Czech Ť are transitional between Polish/Czech T/C. Proper linguist might put some more light on it than just my speculation.

Those overly negative comments often come from USA. I’ve never had any major problems with self checkout in Europe and I generally go there as it’s faster and you don’t have to race against the cashier. Of course some chains have worse self checkouts, some have better but overall many people like it a lot. Even some older people who are not tech savvy use them.