You "glossed over" the most interesting (and perhaps most 'damning') move Novell made, and that involved Unix System V Release 4 (SVR4). AT&T owned outright all Unix source code. For reasons not fully understood by me, Unix fell under copyright (not patent protection).
For AT&T, Unix was a "cash cow" -- they "took a cut" from the sale of every Unix license sold anywhere in the world (regardless of "flavor" -- BSD, AIX, NeXTstep, Ultrix, Irix, HP-UX, Solaris, SunOS, etc.).
AT&T had been a federally regulated monopoly since the Communication Act of 1956. Unlike most monopolies, profits were regulated, not rates -- leaving innovation entirely up to AT&T. By the early 1980s, the United States had the best telephone system in the world -- but the world was changing and the absence of competition was stifling innovation.
AT&T divested itself of its subsidiaries under a consent decree as a part of the Communications Act of 1984. But that wasn't enough. In order to branch out into broader, non-Telco, areas, AT&T needed to divest itself of control over Unix.
Novell's buying the Unix Systems Laboratories "cash cow" might have been a smart move had they not turned around and sold off perpetual licenses to all the big players in order to recoup their investment on as short a timeframe as possible.
Sun Microsystems was the first to buy in. Then again, Sun had "partnered" with AT&T to developed SVR4 in the first place so their rights to SVR4 were already extensive.
By the time Novell had sold off perpetual licenses to all the big players, the value of the intellectual property of Unix had diminished to almost nothing. By selling off the last of it to Caldera/SCO, there was nothing left for SCO to sell because all the vendors that mattered already owned perpetual licenses.
Novell WAS smart enough though to retain their rights to the original SVR4 source code. With this in hand, Novell is pretty much free to do as it pleases with whatever intellectual property still remains in that SVR4 codebase.
Since their acquisition of Sun Microsystems, the only other player with similar rights may well be Oracle -- but they seem entirely uninterested in leveraging their Solaris assets.
Whether Novell's having played their Unix cards differently would have made a difference with regards to the success of Linux is irrelevant today. Similarly, were Unix originally protected by patent law instead of copyright law, Linux might not even exist today. It certainly would not be a Unix "clone."
I may be wrong, but as I remember, it was Ray Noorda that had the obsession with Microsoft. After he retired, Novell seemed to come to terms with Microsoft. Ray couldn't stay retired, though, and started Caldera.
As I recall, Caldera bought the Santa Cruz Operation, a respectable Unix reseller, and changed the name of the combined company to SCO.