We will have to agree to disagree on the interpretation of Buffett's statement 'revenue moat with an honest leader' and what it means.
As far as what is good for society(consumers) regarding business, monopolies are rarely good. People should keep this in mind when there is gov takeover of a sector. State run ___ almost always ends up with less for more cost (whether paid directly or indirectly). Standard Oil over a century ago or Microsoft 2 decades ago, the effect on pricing and quality can be dramatic.
But to take the only US (close to)monopoly I personally know of as an example: Google's 90+% web search business. Has it been bad for consumers? IMHO from a security privacy perspective yes(but that's not per se due to the monopoly) but from web search availability and advances? Arguably once could say it has been a boon to the web search capability for consumers.
But consumers are dreaming if they think: A. a big business will not use its deep pocket leverage. That can be bad but it can also be good (quicker downward pricing pressure for example) for consumers. B. that there will never be big businesses that can leverage their deep pockets, infrastructure, or deep customer penetration resources. Most business spaces start out with many but it gets whittled down to a few ](in the supply chain it can get whittled sometimes to one). In free enterprise it isn't likely to happen any other way than growth of sector to big business status . C. Consumers themselves make this choice. If you can educate them and get others to, a difference may be made.
Yep, let's agree to disagree on Buffett's statements.
There are many other monopolies than Google search. Not sure why you think that is the only one and then in the same post point out that on the supply chain there might only be supplier. Anyway, here is a weird little monopoly: cheerleading. Sure, consumers have a choice. You can not do cheerleading team. That is basically your choice. But you can't do cheerleading team and make that your thing that you do in a serious way in school and not pay Varsity sports (bought by Bain Capital for $2.5 billion). They run the sport, 80% of the tournaments and sell the uniforms (which are basically mandated uniforms). Their goal is monopoly power and then set prices that the kids/parents pay.

How a Cheerleading Monopolist Played Rough During the Pandemic
After mass layoffs, Bain Capital's Varsity Brands is now a "cash flow" machine. It also faces risks from an increasingly angry cheer community.

Yep, companies left unchallenged by laws will eventually aggregate and seek to get bigger. Why do you think that is? It is because monopoly power is where the best profits come from. They all want to get to the point that Buffett lays out as the ideal situation (from the business or investors position): have a monopoly where you can dictate price to your customers without too much worry about quality.