US 17.75% vs Europe 15.59%, if this is what you mean by "ahead"., the US is actually ahead of Europe in terms of 5G IP.
All this kind of statistics must be read very carefully and may not reflect the truth because there may be different "truths". One thing is "IP being more applicable to a specific region or country" such as mmWave which is a US thing with little adoption outside US. US companies have very high portion of their IPs in this area does not make them leaders in 5G global. Just look at the 3G and 4G, US eventually abandoned their 4G standard adopting European 4G. Same happened to Japan's 2G attempt. Those American and Japanese IPs never had any impact outside home.
The IP must be measured against their adoption ratio in the world market. Now if you break down this 17.75% into world IP and US-exclusive IP, the ranking may turn around.