Can my PSU support the RX 6900 or RX 6800? New to PC gaming and building.

[James Herbert]

Hi, I'm fairly new to PC building and upgrading. I'm looking to nap the RX 6900, or RX 6800 in the future. I read the minimum wat for the RX 6900 is 850 W, and the minimum for the RX 6800 is 750 W, at lest according to the website.This is my PC.Now, I realise I have a 750 W PSU, but I've read the some people say not to be too concerned with a minimum wat on a GPU. Even when I've used various online PSU calculators, and included my build, along with the 6800/6900, is says I need 600 or less wat across several tests.

• 1 x Lian-Li Lancool II Mesh RGB Midi-Tower Case - Black
  
  
• 1 x MSI MPG B550 Gaming Edge WiFi (AMD AM4) B550 ATX Motherboard
  
  
• 1 x AMD Ryzen 9 3900X Twelve Core 4.6GHz (Socket AM4) Processor - Retail
  
  
• 1 x Scythe SCFM-2000 FUMA 2 Dual Fan CPU Cooler - 2x120 mm
  
  
• 1 x Gigabyte GeForce RTX 2070 SUPER Gaming OC 3X 8192MB GDDR6 PCI-Express Graphics Card
  
  
• 1 x Super Flower Leadex III 750W 80 PLUS Gold Modular Power Supply - Black
  
  
• 1 x Team Group Vulcan Z T-Force 32GB (2x16GB) DDR4 PC4-25600C16 3200MHz Dual Channel Kit - Grey
  
  
• 1 x WD Blue SN550 1TB NVME M.2 2280 PCIe Gen3 Solid State Drive (WDS100T2B0C)
  
  
• 1 x Seagate 2 Tb Barracuda 7200
  
  
• 1 Gaming Mouse
  
  
• 1 Gaming Keyboard
  
  
• 2 Monitors (1 22'' - 1 28'')
  
  
• 1 USB charger (my fitbit)
  
  
• 1 USB charger (PS4 Controller)
  
  
• 1 Headset

So, explaining it to me like I am five, why exactly are some people saying not to worry about the minimum wat. but the website gives a minimum?