It is now confirmed that Windows 11 is a 64-bit operating system, unlike Windows 10, which was available in both 32-bit and 64-bit architecture. This means any PC or a laptop with a 32-bit processor will not be able to run Windows 11 OS despite having all the other requirements of Windows 11 OS.
64-bit is the latest computer architecture that is used across computing devices like PCs, Laptops, smartphones, tablets, gaming consoles, and more. A PC with a 32-bit architecture processor will have all the data like memory address and integers in 32-bit integer or four octets. It can store a maximum value of 2^32 and can only use 4GB of memory at max.
Similarly, a 64-bit architecture will have 8-octet and can store a maximum value of 2^64. It can support up to 16 Exabytes of memory which means, 64-bit architecture will remain as a standard at least for the next few decades, at least in mainstream computing. Hence, 128-bit computing could be limited to super computers.
Due to the limitations of the 32-bit architecture and given the number of active 32-bit architecture computers, Microsoft might have decided to make Windows 11 OS a 64-bit only operating system. Hence, anyone with 32-bit architecture-based computer won't be able to enjoy Windows 11 at all.
Do note that, Microsoft was actually one of the last major OS developers to stop supporting 32-bit architecture. However, Windows 11 still supports 32-bit apps and software. This means you can still download on install a 32-bit application on a computer running Windows 11. Do note that, the latest version of the macOS does not even support 32-bit app installation.
If you bought a new Windows laptop or a PC in the last 6/7 years, then it is highly likely that it will be a 64-bit architecture-based computer. Hence, there is nothing to worry about the same. However, if you have a legacy device, which is more than 10 years old, then, there is a possibility that the computer might be using a 32-bit architecture and might not support Windows 11.