You can look at it the other way around: GDPR can be a barrier to entry in the European market, therefore making EU compagnies more resistant to outside competitors, which increases their valuation.
As a foreign company, if you want to enter the European market you can either comply with GDPR (which honestly is not that hard despite all the FUD), or take a stake in an existing EU company, provided you let it continue operating as it currently does or at least in a GDPR-compliant way. Buying a EU company to siphon off its customer data (even if it’s just to merge with your own platform) is a big no-no, unless you yourself are GDPR-compliant.