Don't get your information from youtubers. Way too many people out there doing things for clicks and likes, people exaggerating for shock value or dramatic effect, too many conspiracy theorists and other filler you should sift through when getting your information. This time of year, conspiracy theories about feed are very popular, when newbies see a drop in egg production and have no idea what's going on. The number of people who don't know that chickens molt, that chickens rest in the winter, and other basic chicken facts, is mind-boggling. The fact that chickens lay through their first winter is extra confusing to such folks. But my hens laid last winter, why aren't they laying now? Clearly somebody's out to get me!
Brand makes no difference at all. What matters more is protein %, added calcium or no added calcium, fresh vs. stale feed, etc. If you notice differences in shell quality between brands and you're only feeding layer feed without supplementing additional calcium, it could be that some brands add more calcium to their layer feeds, and others add less. If the feed is especially low in protein, like 15-16%, the hen's body may not have enough to meet all of its needs - overall health, molting, and laying - and may start to prioritize by reducing the laying. If the hen is actively molting, that takes priority over laying no matter how much protein you provide. Same with daylight - if her body decides there isn't enough daylight to support laying, she'll stop even if she has the best feed in the world. If you want to maximize egg production and overall health, feed a 20% protein feed that has no calcium added (so an all flock type of feed), and have calcium available in a separate container at all times (crushed eggshell or oyster shell). That way the chickens can regulate how much calcium they consume - they are very good at knowing how much they need - and you'll reduce the risk of thin shells or calcium buildup issues associated with consuming too little or too much calcium.