If Raven Bloom Student is on a battlefield, and you play a spell like Stupefy, but it gets Hard Bargained, does the Stupefy still count as being played, allowing Raven Bloom Student to go up a Might from a spell being played?

No, Ravenbloom Student will not gain +1 Might in this scenario.

According to the established rulings for Ravenbloom Student (such as FAQ #7187 and FAQ #2377), a card is only considered "played" once it fully resolves. If a spell is countered—whether by a card like Defy or by the effect of Hard Bargain (if the controller fails to pay the cost)—it does not resolve, and therefore it is not considered "played."

Sequence of Events:

1. Play Stupefy: You place Stupefy on the chain.
2. React with Hard Bargain: Your opponent plays Hard Bargain targeting Stupefy.
3. Resolution of Hard Bargain: Hard Bargain resolves. If you choose not to pay the [2] cost, Stupefy is countered.
4. Result: Because Stupefy was countered and did not resolve, it is not considered "played." Consequently, Ravenbloom Student’s triggered ability does not activate, and it does not gain the +1 Might bonus.

As noted in the retrieved FAQs, this rule is consistent across all counter-effects in Riftbound: if a spell is prevented from resolving, it never reaches the state of being "played" for the purposes of triggered abilities.