Can PH be used as the sole tool for product publicity throughout its entire lifecycle?

Definitely not. You need other channels to grow your product and scale it to the point where it becomes profitable.

I believe PH can boost your product's visibility, but relying on it alone is not a good strategy.

I'm also new to marketing. I know about promoting with PH because a senior told me about it. I don't know what other people are talking about when they mention channels. Can anyone give me some specific examples of promotional tools that are comparable to PH?

Agreed, just relying on Product Hunt isn't enough. You definitely need a multi-channel marketing strategy to really grow and scale a profitable product. PH is great for initial exposure and attracting early adopters, but to reach a mainstream audience and drive consistent growth, you've gotta leverage other channels too like content marketing, SEO, paid ads, etc. Building in virality and referrals can also help a ton with organic growth beyond the PH launch.

PH works well for initial buzz, but other platforms are needed to maintain momentum over time.

Not advisable... At all... you need to combine with other platforms