@Scott44 Maybe you could revise your wording to these inappropriate inquiries that go on to submitting a booking request. "Can you revise your request?" is obviously not being understood as a "We can't accept the terms of your inquiry" so I'd find another way to make it evident that you will not accept a booking from them under the conditions they are proposing, or without them inputting the correct number of guests. In other words, don't ask them to do something, tell them they have to if they want their booking accepted.
And if it's just a matter of not ever getting any response from someone after you answer their Inquiry, that's quite common, and I wouldn't waste your brain cells wondering if it's a slap or a mistake, or just being rude.
The examples you gave are different from one another. In the case of a guest asking you to waive your cleaning fee, or otherwise lower your price, when you answer that that won't be possible, and they go on to submit a booking request, that means they are accepting the price as is. It's up to you if you want to accept them or decline them simply because they tried to see if they could get it cheaper.
If a guest enters the wrong number of guests, a return message like "HiXX, It sems you may be unclear on the booking process. You've indicated you are travelling here with your wife and children, therefore you need to enter 4 guests, not one. Unregistered guests not accounted for on the booking will not be admitted to the property, which of course would be disastrous for you. So change the guest count to the correct one and resubmit your request, thanks."
The ones who enter wrong dates and hold your calendar hostage have probably done that on a few places- holding them all until they decide which one to actually book. Those guests are a right pain. Message "Hi XX, please ensure that the dates you have entered on the booking request are the actual dates you want to stay, as once I accept, your credit card will be immediately charged." This may prompt them to withdraw the request, opening up your calendar and eliminating the need to decline.