buy computer now with new software on the way in fall?

I have never had a problem with updating a Mac computer or with an update resulting in slower performance. Apple has a history of releasing major updates for Macs once a year and several minor updates during the year. I wouldn't hesitate to buy now just because of an update coming this fall. However something that I would consider is that Apple typically releases some new models in the fall each year and if you want the latest and greatest hardware, that possibility may be a reason to wait.

chorky1:

Be aware of hardware limitations on performance; with newer releases of computer, that are

key to better usefulness and costs of admission to get higher level best configuration to use

with the Apple silicon evolution underway. Impressive specs, though, these models highlight.

The early releases of M1/M2 and step upgrades to fine-tune the macOS via updates, are

critical too; since with the hardware, you buy into the performance level per pricepoint.

Many of Big Sur update steps have been needed to adjust a newer hardware match and

set the bar higher, for better use of new Silicon M1/M2/x. ~ At an affordable level, those

least expensive early M1 units aren't foolproof, or anywhere near trouble-free just yet.

Updates/upgrades aside, third-party 'pro software' is still playing catch-up; and so on..

At least the big bugs are getting worked out with Big Sur. Ahead of a newer batch in

macOS Monterey12.

To clarify, there is no 13" MacBook with the M1 processor. There is a 13" MacBook Air and a 13" MacBook Pro with M1 processors. The last MacBook was the 12" 2017 model that was discontinued over 2 years ago.

Over the last decade or so, Apple has released new versions every year.

These macOS upgrades can require you to update your apps.

Apple doesn’t target legacy hardware and legacy software compatibility and support to the same degree as does Microsoft. Developers and third-parties are expected to update their apps. If you want or need to run older stuff for longer, Microsoft can be a better choice. (There are folks unhappy about having to replace their Microsoft Office 2011 purchases with newer Office versions or alternatives, as that app and other apps using the now-deprecated 32-bit interfaces that were retired and removed with macOS Catalina 10.15. Apple had been warning about that deprecation for a while, though; since 10.13. That 64-bit migration started a over decade ago.)

Various third-party app vendors for macOS support the three most recent versions. Some support older.

M1 is clearly focused on entry-level and low-end configurations, with current M1 models differing largely in the numbers of ports available with more ports in the higher-range models, and in better cooling for better sustained performance in the case of the MacBook Pro. What comes next for Apple Silicon, we will learn.

Buying: There are no memory upgrades and no internal storage upgrades after purchase. For longest usage, order the 16 GB M1 configuration and not the 8 GB, order more storage than you think you’ll need over the next five years or so, and expect to be fine for five years and probably longer

Also expect to order a 4 to 6 terabyte hard disk drive for backup with Time Machine, or a NAS with Time Machine support if you have the budget for that.

You might expect to order a dock or dongles, depending on which I/O connections you need to make, if those connections are not wireless.

MacBooks were discontinued over 2 years ago. Current models are MacBook Airs or MacBook Pros.

There are no M1 MacBooks, perhaps you mean a MacBook Air or MacBook Pro.