Nobody gave you the actual answer. IBM was under an antitrust decree and had to openly license their technology for a nominal fee. (Supposedly about $5/PC.) So yes, they were in a hurry and used generic parts, but they still had tons of patents on it. When they got out from under this, they came up with Microchannel.
I guess antitrust is the keyword here. Something that is considerably weakened in today's USA.
IBM had/has a monopoly on mainframe systems. But they never were really dominant in midrange systems (e.g. VAX, UNIX), and Microsoft and Apple etc became huge companies in the PC market. So you can't really disagree with the rationale.
Obviously Google + Phone makers is a "trust", its frustrating the lawsuits aren't really going anywhere.
I continue to be of the opinion that many of our economic problems could be improved with more competition. (Depending on your definition of "problem" of course. The current state of affairs is fantastically profitable some.)
Oh for sure. Why are movies scattered all over oblivion? Because there's no simple marketplace for licensing movies, it's a closed market that requires doing lots of behind-the-scenes deals. Healthcare? Only specific providers can make medical equipment, tons of red tape, opaque billing structures, insurance locked out in weird ways, etc.
To understand how healthy a market is, ask 'how easily could a brand new startup innovate in this area'. If the answer is 'not easy at all' - then that thing is going to be expensive, rent seeking, and actively distorting incentives to make itself more money.
This and also cryptography technology was not nearly as sophisticated and easily accessible as it is today, and where it existed it was pretty slow on the hardware of the time.
How much of it is cryptography? The only notable cryptographic locks are just the TPM-backed Widevine and the infamous Play Integrity, both rarely required due to how many older devices that would lock out.
There's no crypto, as far as I know, in all the binary blobs in the kernel, yet we still can't re-implement enough of them to even have a true Linux phone without reusing the manufacturer's kernel.
Secure Boot (or whatever it's called on each hardware platform) relies on trusted cryptographic keys to sign "the next step" in the boot chain, all the way back to the bootrom. This is how the higher-level SafetyNet attestations work on Android, and equivalent features on iOS, XBONE, etc.