Euro syn oils are rated to a different standard, and typical US API certifications don't apply. Most SN oils will breakdown in no time in a lot of European engines. The BMW's, for example, are more like old American stuff. They use bucket lifters with direct cam>lifter contact, so they need a higher ZDDP oil than say, a Toyota or a GM thats a full roller valvetrain. It also requires a more shear-stable oil. A3/B4 oils typically have an HTHS rating of 3.5 or higher. M1 5W-30 will shear to a 20 wt in a matter of miles in a BMW engine that sees redline once in awhile. They also run, for the most part at least, a larger sump and higher oil temps, and see heavy rod bearing loading (sometimes with an inadequate rod bearing - but thats a typical for a whole other discussion.
Also of note - not all Euro ratings are the same either. Most of the manufacturers have their own specs, but most of the Euro rated oils are similar. Beware - Euro gasoline & diesel, like the US, are a completely different spec, except they aren't nearly as cross-compatible as US ones are. Rotella can be ran in damn near anything and be happy. An LL-04 BMW rated diesel oil, otoh, isn't the case.
Lubrizol is an additive manufacturer, and has a really nice tool to let you compare most of the oil specs on the market and how different their areas of focus are.
https://www.lubrizol.com/Lubricant-and-Fuel-Additives/Engine-Oil-Additives/ACEA/Relative-Performance-Tool