I spent like 20 minutes trying to research how to do this without trying to copy paste from the floating “Data Table” window in My Maps. I couldn’t find anything that didn’t involve logging into an unknown website or downloading an app, so here ya go:

In Google Chrome, open the data table and right click somewhere at the start of the table and choose “Inspect” to open the code view.

Find “table-container” in the panel.

Right click the table-container line and choose Copy > Copy Element.

Visit w3schools.com and click “Try It” to open their quick view code editor.

Paste in the code in the window on the left.

Click “Run >”, and you can view your table. It might look a little wonky but it’s good enough for a copy-paste. Copy the data from the window on the right.

Paste into Google Sheets, Open Office Calc, Excel, etc to view as a spreadsheet.