You're absolutely right.
Given that ICANN depends on volunteer communities throughout the organization, it would strike me as obvious that the org would cover the cost of whatever tools would be necessary to enable these communities to properly engage. Making communications pay-to-play defeats the core claimed benefits of multistakeholderism.
Being a nonprofit ICANN has access to substantial discounts on conferencing tools including Microsoft Teams, Google Meet and Zoom. I personally don't care which. Why such procurement is even an issue of any controversy or delay boggles the mind.