I can help you get better landing page feedback (by asking the right questions)

Yay! This sounds like a great product

Before I suggest some questions to ask, let's talk about assumptions that we're making about the page in the "Things I want to learn" section

Assumption 1: the current page is describing the problem and the solution
Assumption 2: indie hackers, product managers, marketing folks and user researchers all share the same job to be done for the product and their motivations for using the product are the same
Assumption 3: too many words!

Are those assumptions correct? I would say (probably) not.

[1]: I know what Listener does + the outcome(s) of using it. The problem is implied (not necessarily a bad thing - but some of your target audience segments may not be as clear on why Zoom call highlights are a great idea as others)
[2]: I'd say no (and it sounds like you're wondering about it based as well)
[3]: see Rule of One below - but we can test that!

Battle-tested best practices say more specific = better (see Rule of One here: https://www.theagentsofchange.com/joanna-wiebe/).

That aside, let's look at the questions and find a way to answer them. In this case, I'd actually suggest setting up a survey - but you could use the questions to ask for feedback as well (organizing it would be quite painful, though).

• Is the copy communicating the problem and solution well?
  Questions:

Based on the information available in the hero section, what do you think is the problem this product is solving?
Based on the information available on this landing page, what does this product help its users achieve? [
What would you say is the biggest benefit of using this product? [testing for what people take away from reading the page - if it's "too many words," then we may notice some confusion here]
Based on the information available on this landing page, who would you say is this product for? Name as many types of users as you like. [Is it clear who this product is for?]

• Can I say it in fewer words?
  Questions:

Do you have any questions about the product after reviewing this page? [Do we actually need more words?]
Was anything unclear? [Do we actually need more words?]
On a scale from 1 to 10 (10 = strongly agree, 1 = strongly disagree) , how much do you agree with this statement: "This page has too many words!"
[I think that this is not a good question to ask, because the amount of words is determined by the audience's stage of awareness, and this question is very much a "like/ not like" question - but it can give you a ballpark for the page perception]

• Is there a need to narrow the scope to reach specific audience?
  Questions:

What's your job title?
On a scale from 1 to 10, how relevant would you say is this product for your day-to-day life (1 = not relevant at all, 10 = very relevant)?
You chose "Number" - can you tell us a bit more about the reasons you chose it - there are no wrong answers here!