Ever done theater? If it is your job, getting bored isn't an excuse.
I get up and "perform" almost every week during new employee orientation. You're right, it's not that hard to fake it when you know what you're doing. How many people in customer service roles fake it every day?
I know there are folks active in ENWorld who are much more keyed into the TTRPG industry and know better how the economics of TTRPG publishing works. Am I missing something obvious on why this kind of approach wouldn't work?
I think what you're missing is the cost of labor versus the expected return on investment. I've been reading a lot of Chaosium books lately, so let's just pretend they want to start a GMing service for their games Call of Cthulhu, Pendragon, Runequest, and 7th Sea. We're going to hire Herbert West to exclusively run Cthulhu games. And let's keep things simple, this is going to be an hourly, part-time position, so we're not expected to provide Dr. West (he's a physician) with employer benefits like medical, dental, or vision insurance.
How much do we pay Dr. West per hour? I'm going to be very generous to the company here and say we'll pay West $20 per hour and we expect him to work an average of 20 hours per week. But then we need to remember we're obligated to pay federal and sometimes state and/or local payroll taxes. I'm not actually in payroll, so I don't know all the associated expenses, but let's just be generous and say in addition to the $400 we expect to pay West weekly we can tack on another $80 in expenses. So in payroll expenses alone, we pay West $480 a week (that number should probably be higher).
But that's not all it costs the company. We've got to have company infrastructure to support West and the other GMs. We need someone to recruit candidates, someone to supervise them, they need gaming materials (scenarios, rule books, etc., etc.), an online infrastructure to facilitate remote gaming, and you'll need someone in HR/Payroll to deal with employees scattered throughout multiple states. I'm not exactly sure how to calculate the cost of all this.
What's the return on investment for us hiring West? Remember, we're doing this primarily as a means to generate revenue rather than viewing it as something like an advertisment expense or something like that. Let's say we expect to generate $960 in revenue from West's work. How much do we need to charge for each session to remain profitable? West needs to make us $48 for each hour he's working which means we have to charge our customers $9.60 per hour (assuming a group of 5). To simplify things, we charge each player $38.40 for the session and it lasts four hours. Sometimes you might not have a full group, but we'll say the minimum is group is 3, in which case you won't make that whole $960 each week unless West has that full table 5 days a week.
I cannot stress enough that my numbers are weaksauce. There's all sorts of complications including make sure your customers are happy in addition to all the other costs associated with doing business. I personally don't think it's worth any company's effort to try this as a line of business.