The study: https://www.pnas.org/doi/full/10.1073/pnas.2304099120
There are some buts though, where the article also hints about. If e.g. your home is not well isolated against cold or warm weather, it may be more efficient to all go to one place that has this better covered.
Itβs in Dutch, but your favorite translation service can help out.
Also, it is important to consider that many large video conferencing companies (which are mostly profit-maximizing) are not interested in reducing emissions. Those programs not only broadcast meeting data, but additional, excessive information that comes from telemetry, which creates more pollution.
Therefore, if you use Nextcloud or any other locally-hosted platform, emissions will reduce by a lot, because those programs only run what is necessary. The user is in control of what apps that instance can have, and therefore, partial control of emissions.