I believe the H tags has or is morphing into a semantic tag question. Search engines don't automatically give a benefit for using H tags as in the past ... they care about what visually should be the H tag and use that instead! But they do care about semantic usage, which is why they look but verify, and reward those who they choose.
Some history helps explain best usage.
The H1-H6 tags are the original semantic tags used to create an outline of the content. They are used by screen readers for people who have difficulty in reading the content or in some cases may prefer to have the page read to them.
The best practice is one H1 tag with the idea of two having been
considered. Many sites want to have their company name and the page
title in H1; reasonable people don't see a problem with that.
In the good old days using H tags for keywords worked well, but now that the robot can render the page and determines what is important by design factors such as which content is actually the most predominant ... and it the good old days method does not work. [see note below]
Benefits to using semantic tags
While the H tags no longer work as they did in the good old days. Search Engines do pay a lot of attention to usability, including if the text is large enough to read or if links are to close together for usage on a cell phone.
If there were no advantage today, (although i say if, many have evidence of an advantage [note below]), to making a site that worked well for more people the chances are high that in the future it will. So evergreen content should use these tags. It is the direction the search engines are trending towards.
For any vertical in the Search Engines algos are being applied differently. Some sites are ranking because of fresh content algo while others are ranking because of YMYL, (your moneny your life), historic authority content. You know those http not https sites that still show up, they don't need H tags.
Some people may see a significant change and others nothing for the same type of change to their content. I can literally rank any content on a YMYL site, but don't because too much to lose. On that site H tags have zero effect. On another site it almost does not show and H tags are important.
Since the effect is not consistent people are expressing what they have seen. I advice to consider where the trends are heading, the algos are trending towards better readability and if the H tags don't express this it is best not to use them ... if they express it then it is best to use them.