Proprietary Software is Anti-Capitalist
A theoretically perfect market under capitalism assumes that consumers have access to an infinite supply of producers. This allows consumers to inspect the market, and select the product that best fits their needs. In the long term, monopolies erode capitalism, because they meaningfully constrict the market and decrease the options available to consumers. This means that consumers have limited access to a variety of products and services under a market controlled by a monopoly.
A patent is a construct that grants a company a temporary monopoly to produce something. This is based on the assumption that guaranteed monopolistic power for a temporary period can encourage innovation. Some assume that proprietary software licencing can encourage innovation in a similar way. However this is not the case, because the proprietor of a piece of software actually has a permanent monopoly on the marketable actions to that software, such as distribution, repair, and modification.
The key difference between Free Software and proprietary software for the average consumer is not that they have the right to view the source code and learn to repair or modify their own software. The difference is that the consumer can access an unrestricted market of software developers to make the modifications or repairs to the software that the consumer desires. This is no different than a consumer bringing their car to their mechanic of choice in order to repair or modify their vehicle.
Should you be interested in finding support for Free Software, or if you are interested in providing service, the Free Software Foundation has put together a list of services that could provide assistance. You could also reach out to freelance software developers on sites like Fiverr, or Upwork.