Just added to the above linked thread.
"The legacy call recording and switching phones during a call were both functions built into the old Google Voice PBX infrastructure. They are some of the only functions left on the old PBX, which is costly to maintain for just that purpose. The new Google Voice for Workspace has call recording as part of the Google Workspace infrastructure, designed for industries that need regulatory compliance (like financial and healthcare). It isn't usable on a Gmail account.
The old call recording feature is expected to be gone in the coming week, unless some last-minute issue crops up."
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