You often hear that Linux will only become mainstream when more proprietary software is ported to Linux. Like the two characters waiting for Godot, thousands of people are apparently waiting for the day Microsoft Office or Photoshop releases a Linux version and demolishes its free-licensed rivals. Against all reason, the expectation persists.
The truth is, proprietary ports are unlikely to happen. Commercial software developers have never figured out how to profit from Linux ports. Meanwhile, in their hesitation, countless free software equivalents have matured into serious competition, providing another reason the commercial shops to avoid the market. The only exceptions are high-end products like Maya, which can be written off as a business expense.
So why do people persist in the idea that Linux needs proprietary apps? A failure of imagination may be one reason. Thanks to Microsoft and Apple, software has been viewed as a commodity since the early 1980s, and alternative ways of thinking are inconceivable for many.
In fact, so far as the average user knows Linux at all, they are relying on long outdated myths. On the one hand, they expect Linux software to be hard to install and crude compared to proprietary applications, because that was the case twenty years ago, and they have no hands-on experience that might tell them things have changed.
On the other hand, they have heard the pro-Linux myths, such as the claim that Linux makes anti-virus software and defraggers unnecessary. Some may learn that such claims are exaggerations, but for most, the claims are so contrary to their experience of computing that they reject them without bothering to investigate. So far as many are concerned, if you run a computer, using anti- virus software is an inescapable necessity, and anyone who claims otherwise must be a liar or at best a naive enthusiast.
Conditioned to be consumers, average computer users know without the need of any experience that software you pay for is superior to software you download for free. They know, too, that software for sale in a store and software with a brand name is more trustworthy than software available on line or software they have never heard of. Admittedly, some free software like GIMP or LibreOffice has struggled to a limited brand recognition, but such successes are minor compared to well-branded software such as MS Word or Illustrator.
From such myths and expectations, it follows that an operating system (whatever exactly that is) without proprietary apps cannot possibly be worth any attention. It is like a no-name breakfast food in generic packaging, barely noticeable next to the big brands. By contrast, average users may curse Microsoft, or insist that Apple has gone downhill in recent years, but at least Microsoft and Apple are familiar.
Having users actually try free software rarely changes such attitudes. With low expectations, their explorations usually become self-fulfilling prophecies. If a feature has a different name in Photoshop than it has in Krita, instead of looking for a near-synonym, they are apt to conclude that the feature is missing. So, too, if the feature is in a different menu. If the feature is not immediately obvious, then they conclude that it does not exist -- which is what they suspected all along.
The trouble is, most users have learned Microsoft Excel rather than spreadsheets, or Adobe Illustrator rather than vector graphics. That is, they have learned particular pieces of software rather than what to expect in any given category. They are unprepared to learn software that is organized slightly differently. Nor after using near-monopoly proprietary software are they accustomed to alternatives.
For example, if they find that GIMP is unable to do four-color separations, few are willing to check whether Krita does. Chances are that they don't know that Krita exists, or where to look for alternatives. Instead, their conclusion is likely to be that free software graphic programs on the whole cannot handle four color separations. Since their low expectations are fulfilled by this conclusion, they see no reason to test them.
Such attitudes are often reinforced by the assumption that the best tools are the industry standards. If the graphics industry depends on Photoshop, then clearly it must be the best tool for manipulating graphics. Explaining that GIMP or Krita may have features that Photoshop lacks is typically useless, because Photoshop is just as likely to have features that GIMP or Krita lacks. Nor can you argue that the free tools are suitable for professional work because you have used them that way; your personal example will probably be dismissed as a special case that does not affect the sweeping generalities.
Like Creationists arguing the non-existence of transitional forms, users sometimes have to resort to a feature as minor as a pre-defined keyboard shortcut to justify their position, but that hardly matters. Never mind that the free software allows users to define the shortcut for themselves -- what matters is that the preconceived notions with which most users approach free software have been reinforced, no matter the degree of desperation or distortion involved.
Instead of being a meaningful comment, the need for proprietary software has become an excuse for not changing, or even investigating an alternative. It is a rationalization, not a reasoned argument, and is typically defended by any means available.
That is why, these days, I rarely bother to argue against such a position. It would trying to pry open a close mind, and experience long ago taught me that such efforts only waste time.