Potentially, the phrasing; "I don’t believe that our own improvement and growth should be treated as a hobby or interest reserved for a select few" has an ominous meaning.
Actually, it is a form of a veiled threat.
What it says is that you will not be free to choose your own "Self-Improvement". It means that Self-Improvement is something that some external agency can impose upon you.
A governmental agency would be one obvious external agency.
. Therefore, the following statement should be modified to represent the actual meaning or the statement of believe that you quote:
"Self-improvement is something that everyone should be able to engage in."
This is what a person in a democratic society would "read into" this statement of belief or write, . The correct meaning being conveyed is this:
"Self-improvement is something that everyone MUST engage in."
This is not inviting you to engage in "Self-Improvement" as though it is some sort of social privilege as a segment of the population viewed as a privileged few. This is why the statemtent of belief offers a reference to a person choice, such as a "hobby". Hobbies are interests that we choose to pursue. So this sentence informs you that the choice to practice "Self-improvement" is not a power that you reserve unto yourself. It is a power than
should be imposed upon you by an external agency.
.
So the author of the statement of belief is telling you, with some rather modest language, that you should be subject to others dictating what "Self-improvements" you must make.