Assume an artist (either directly or through a rights holder) makes 1/3 income from streaming, 1/3 from merch and physical albums, and 1/3 from live events.

40m streams per year would be 800k per week. 200k fans worldwide playing 4 times per week on average could get you there. Thats like a decent sized but not enormous youtube channel.

200k fans worldwide would also support the ticket sales and merchandise sales aspects.