I don't know much about enriching ingredients in the US, but where it's done, it's to prevent diseases you can get from missing them, or which can cause other health problems. Folic acid, which is in your list, is well known as a recommended supplement for pregnant women, since it dramatically reduces incidence of spina bifida in newborns. Niacin is better known as vitamin B, and it's a similar story.
In this case the enriched flour in the commercial bread presumably isn’t concerning, but I would prefer bread without added sugar and all of the various preservatives and emulsifiers.
Research is ongoing but shows some potential impact re emulsifiers and their impact on the gut: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9331555/
And some indication that one of the preservatives can have behavioral effects in kids: https://pubmed.ncbi.nlm.nih.gov/12173999/
https://cooking.stackexchange.com/questions/45587/how-did-pe...
It helps that other countries have them too. It's hard to corrupt the entire world. I wouldn't worry (yet) about individual studies claiming some possible interaction, especially if they bunch up manky things (say, aim to study all emulsifiers at once, or all processing at once).
I would worry if, say, an additive was banned in many countries. And there's much that we know is bad, which is permitted for cultural reasons, and which therefore many people assume can't be that bad (smoked food in particular).