"Open source software depends on the contribution and altruism of the software development community to create and enhance software so that it can be provided for free."
"This is because while many companies like the concept of free software, they still need to be able to call someone for support."
In these two statements you seem to be missing the distinction between gratis and libre. Free and open source software is about free as in freedom (libre), not free as in cost (gratis). Free software (libre) is quite often not developed for free (gratis) even though it is most often distributed for free (gratis) since not many people will pay for software that others who have already received a free (libre) license are free (libre) to distribute the software to them for free (gratis).
This is not just a semantic distinction. Based on this mistake, you assume that free software (libre) is created and enhanced purely out of altruism. There are, in fact, many reasons why free software (libre) is created and enhanced, only one of which is altruism. For example, Red Hat pays its developers to contribute to open source software so that they can continue to sell copies of RHEL (one could argue that they're actually selling "subscriptions" but that's not the point) - note here that free software is being sold for profit which is not at all against ideals of free and open source software. It benefits Red Hat, as a for-profit company, to contribute to open source so that there is a healthy ecosystem from which they can receive the benefits of other's contributions. I could go on enumerating other possible motivations for contribute to free and open source software, but you get the point.
"Open source software depends on the contribution and altruism of the software development community to create and enhance software so that it can be provided for free."
"This is because while many companies like the concept of free software, they still need to be able to call someone for support."
In these two statements you seem to be missing the distinction between gratis and libre. Free and open source software is about free as in freedom (libre), not free as in cost (gratis). Free software (libre) is quite often not developed for free (gratis) even though it is most often distributed for free (gratis) since not many people will pay for software that others who have already received a free (libre) license are free (libre) to distribute the software to them for free (gratis).
This is not just a semantic distinction. Based on this mistake, you assume that free software (libre) is created and enhanced purely out of altruism. There are, in fact, many reasons why free software (libre) is created and enhanced, only one of which is altruism. For example, Red Hat pays its developers to contribute to open source software so that they can continue to sell copies of RHEL (one could argue that they're actually selling "subscriptions" but that's not the point) - note here that free software is being sold for profit which is not at all against ideals of free and open source software. It benefits Red Hat, as a for-profit company, to contribute to open source so that there is a healthy ecosystem from which they can receive the benefits of other's contributions. I could go on enumerating other possible motivations for contribute to free and open source software, but you get the point.