The situation is fluid and likely to change but, based on available information :
It looks safe to buy
Note that the P30 was announced before Huawei was put on the US trade blocklist (aka its 'entity list'), and therefore continues to have full access to Google apps, services and security updates.
(entity list)... prevented Google from licensing Google Mobile Services (GMS) for new Huawei device models made available after May 16, 2019.
As we explained last week Huawei won’t receive support from Google if any changes they make to their future software builds break compatibility with Google apps.
We reached out to Huawei, though, to clarify if the company can continue to implement GMS into software updates for its existing devices indefinitely without collaboration from Google, and also to find out if existing devices will continue to pass SafetyNet Attestation following an update
(Emphasis added in quotes)
I suggest you keep a track of the XDA blog which is frequently updated and take a decision, if these inputs don't suffice.