This is on a new install of PowerShell 7.0.0 from 2020-03-26:
PS C:\> Get-Help Get-SPOSite -online
Name Category Module
---- -------- ------
Get-SPOSite Cmdlet Microsoft.Online.SharePo…
Get-SPOSite Cmdlet Microsoft.online.sharePo…
Get-Help: Multiple Help topics were found. Use only one Help topic with the -Online option.
Notice the .Online and .online difference in the Module names. I suppose I could delete and start over, however I would rather have someone here save from me that. I don't know if that will make a difference, anyway.