You’re talking about software piracy, which the UK and US, and most of the developed world too, also has strict laws for.

However new games are constantly released for old consoles and often sold as ROMs. Which is completely legal because they own the copyright and distribution rights to those games.

Also modern variants of old consoles will typically use emulation with ROMs approved for distribution, such as:

- The SNES Classic Mini

- The Wii Virtual Console

- The Switch Online, SNES

All of these are official Nintendo products. All of them available in Japan. And all of them use emulation under the hood with ROMs that Nintendo supply and have legal authority to distribute.

You can also take this point further and talk about uses of emulation outside of gaming too. Such as emulated hardware components in a virtual machine.