In short, it’s not a great time to buy a Mac unless you absolutely need one or you need to run Windows on your Mac.
The transition to Apple Silicon ARM processors is as significant as Apple’s move to Intel chips in 2006. Imagine buying a PowerPC-based Mac six months before Apple released its first Intel models. You probably wouldn’t be a happy camper for long. For most users, ARM processing will provide faster and more power efficient computing. This is especially important for MacBooks.
Those users who absolutely need Intel chips tend to rely on their Mac for specialized uses, for example music production or industrial apps. (Apple’s own professional apps are already compiled for ARM.) These professional users won’t be able to hold off forever, as Apple is migrating the entire Mac lineup to ARM over two years. Developers will release their apps for ARM during this transitional period. In the interim, Rosetta 2 should be able to run most apps compiled for Intel. Whether apps incur a performance penalty under Rosetta remains to be seen.
The great unknown is whether Windows will ever run virtualized on an Apple Silicon Mac. We already know that Rosetta 2 will not run x86 virtual machines. So it’s up to Microsoft to sell ARM-based Windows 10. Even then, this version of Windows doesn’t run x64 code, only ARM and x86 code (under emulation).