In this message why is し used instead of から？I thought し was mainly for when there’s multiple reasons for things. Is there another use or reason for it or is it kinda like や, where the other reasons might not be stated?
This し simply means “and”.
It means “Interpreter job can widen your view and make you grow.”
や can’t replace し in this sentence because や can’t be after a verb or adjective. And し can’t be after a noun.
Sometimes し means から(because).
I don’t want to go out today because it’s clod.
When し is used as から(because) like the example above, there’s another reason. I think he may be sleepy.
I don’t want to go out today because it’s clod and I’m sleepy.
In this sentence, I think he has no other reason.
As you state in your question, し is used
when there's multiple reasons for things.
As you also point out:
... or is it kinda like や, where the other reasons might not be stated?
it can be used to imply that there might be other reasons not stated besides the stated one. Therefore, し can be used even with one element:
私の仕事は給料も低いし。In my job, I have a low salary (and more negative things such as overtime, short vacations or whatever item that can be grouped along with 「給料も低い」).
In your sentence, there are 2 items (and there might be more items not stated):
However, it is not clear whether this items are reasons for something or not. To me, it looks like they are just a description of 「通訳の仕事」 Can you provide more context? For example, they could be the reasons why you like the interpreter job:
通訳の仕事が好きな理由は視野が広がるし、自分自身も成長できるよね。The reasons why I like the job as interpreter are that you expand your field of vision, it can increase your self-confidence and so on.
In any case, since there is more than one reason and they might be other unstated reasons, it is used し instead of から.