I suggest practicing over and over again to reduce your anxiety. We all feel anxious when doing a whiteboard or now VC interview where they can ask you anything and you feel like you have to instantly answer.
Oh definitely! Doing high pressure practice in preparation for my last round of interviews definitely helped, and that round resulted in multiple FAANG offers.
VC interviews also seem very high pressure! I've met folks making funding decisions, but never been in the hot seat with them. It does seem closer to the "walk me through your portfolio/a project" interview than a whiteboard interview. Although obviously the stakes can be much higher.
Anxiety isn't related to experience (or actual competence). When it's on the level mentioned, what works is CBT (if you're lucky). That may include practice, but it will certainly not be the only element.
I guess it will vary from person to person. For me, my anxiety is definitely reduced the more prepared I actually am, and the more I feel. Have I implemented all the basic algorithms in the last month in my test language, did I actually run them, do quick sort and other sorts whats the time complexity, then try a series of harder programming projects. Do some of the super common ones like design twitter. Binary search - can you avoid the overflow things when doing the divide by two...
And for experienced people, be ready to say what you left your most recent job, what you gained, what did't work well, is there a noticable arc to your career, if you want a new job type how are you prepared.
VC interviews also seem very high pressure! I've met folks making funding decisions, but never been in the hot seat with them. It does seem closer to the "walk me through your portfolio/a project" interview than a whiteboard interview. Although obviously the stakes can be much higher.