Hi @john john Pter,
The max number of index has been increased to 20 million items as default and you could increase the number by contact Microsoft Support. You could refer to the document
https://learn.microsoft.com/en-us/sharepoint/search-limits
While I don't have a graph about sharepoint and power app improved display large data list, I can confirm that Microsoft has been consistently working on enhancing the performance and scalability of their cloud services like SharePoint Online and Power Apps.
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