There are numerous existing precedents in the PHB which indicate any means multiple.
The confusion here is centered around a single word, emphasized below:
You can communicate telepathically with any creature you can see within 30 feet of you.
Example precedent: If you can cast the spell Animate Dead you are able to send telepathic thoughts to your minions collectively. The spell Animate Dead (PHB pg. 212-213) is explicit in the usage of any and all being separate and distinct. Relevant text below:
On each of your turns, you can use a bonus action to mentally command any creature you made with this spell if the creature is within 60 feet of you (if you control multiple creatures, you can command any or all of them at the same time, issuing the same command to each one).
This is an example of how other abilities and features should be read in the same manual. In this case, any indicates that you can select up to and including all of the minions under your control.
To further support this, pretty much every usage of the word any in the PHB denotes a selection among multiple options. There are literally hundreds of examples, dozens of which exist in the spell category, to peruse.
I am of the opinion that the wording here is indicative of the ability to speak to any creature within its range, which means it's not limited to one. If it was, it would have explicitly stated this in the same manner as a spell like Suggestion does (PHB pg. 279):
You suggest a course of activity (limited to a sentence or two) and magically influence a creature you can see within range that can hear and understand you.
Note that suggestion specifies a singular creature, not any creature within range.
Now let's compare it to a similar telepathy spell, Sending (PHB pg. 274):
You send a short message of twenty-five words or less to a creature with which you are familiar. The creature hears the message in its mind, recognizes you as the sender if it knows you, and can answer in a like manner immediately. The spell enables creatures with Intelligence scores of at least 1 to understand the meaning of your message.
You can send the message across any distance and even to other planes of existence, but if the target is on a different plane than you, there is a 5 percent chance that the message doesn't arrive.
All instances used here are explicitly singular.
The same applies for Telepathy (PHB pg. 281).
What this all suggests is that any is used when you have multiple targets, and the singular is explicitly stated.
So, with all that being said, logical arguments for both interpretations, singular and collective are sound. Ultimately, and lacking official ruling, this will require DM arbitration in your games. Since it's not 2 way communication without the receiver having some telepathic ability or skill, it's hardly overpowered.
I would personally rule it as able to hit multiple targets since the precedent is amply set by other spells and abilities that the usage of the word any is collective, not singular. When a spell is singular, it is normally explicitly detailed in that manner.