While a lot of us hate ads and subscriptions, I have the unpopular opinion that they are generally still viable considering the state of how we use the internet today.
The thing is, I think that if there are ads, there should be the ability to pay to remove them, and if there is a subscription, there should be an ad-based tier as an alternative.
Let your users choose, respect their preference for funding model, and allow them to choose if they want to support a given monetization policy.
Of course, seeing as how they raised $15m from VCs, I doubt this will be nothing but what will inevitably devolve into a pay-for-reach scheme similar to Twitter Blue (or, sorry "X Premium") that just leads to those with wealth getting more engagement, and a louder voice.