The verdict
For a small B2B team running webinars as a regular channel, pick Livestorm. It is built for that job, you can test it on a free plan, it hosts data in the EU, and its pricing follows your audience, not your team size.
If your team is standardised on Zoom, your audience knows it, and you need large broadcasts such as town halls, pick Zoom Webinars. Your hosts already know the interface, and there is no second tool to learn.
I'd pick Livestorm for most readers of this site. If you are on Zoom and are unsure, run the same test webinar in both and compare how registrant data reaches your CRM.