The truth is, the video leaves quite a lot to be desired: it’s dubbed with a pretty weak AI, has several typos, and doesn’t show any proof for its claims. I’m not saying everything is wrong, but it’s not something applicable in all cases either. Not to mention the ridiculous thumbnail, suggesting that 0W20 would get dirtier than others, when that depends on detergent capacity; plus, since 0W20 flows better, it probably cleans even more…
In practice, for short and medium trips in Spain’s typical climate—daily use, commuting to work, or driving between towns—0W20 usually offers better protection, mainly because it flows better when cold. And that’s key before the oil reaches its optimal operating temperature, which can take quite a while, even 15 minutes or more in cold weather (and believe me, it’s true, I have a temperature sensor installed).
Now, in countries with extremely low temperatures, like Canada, some do recommend 0W30 to compensate for more extreme situations, like extreme fuel dilution in the oil due to sub-zero temperatures. In those cases, it might make sense. There’s nothing wrong with using 0W30—I use it myself—but that doesn’t mean it’s going to protect better in most situations.
If I had to trust a video, I’d trust these guys more:
