Let's move in time and share explanation of 26 rather than 6 year old man.
Before we start, we have to answer simple question - do you believe that market price already hit the roof?
If you have positive answer on above then I do not understand why you support the idea of autobid. Here you have two reasons:
1) From economy under perfect conditions and no trading restrictions imposed by regulators/government, market price is determined by the law of supply and demand. The level on which both lines cross each other represents equilibrium. In other words, demand and supply is equal against each other and both parties (customer and supplier) are willing to trade at exactly the same price. There are two additional scenarios: (i) demand for product exceeds supply - product is traded at client's price per given quantity, (ii) supply exceeds demand - similarly, we trade at client's price as clients are not willing to cover the cost of overproduction.
http://www.acting-man.com/blog/media/2016/03/Supply-Deman... <--click link to continue the course.
Now let's consider the impact of autobid on pricing. The supply line remains intact, as autobid is unlikely to have an effect whether you place the player on TL or not. It is rather determined by the cost of replacement. On the other hand, autobid will increase the curve of demand line as number of traders/buyers will increase as all of them can set their max price upfront without waiting till the end of an auction (little tricky, will discuss in 2nd point).
Ultimately, equilibrium price will move up meaning that for the same quantity (i.e. product) we will have to pay more.
2) Imagine scenario when we have 2 users to bid on player X.
user #1: he bids first and established his max price at 100,000. He will not be available on the final day of auction
user #2: he/she (let's support equality rights) bids after user #1 and sets max price at 60,000. He/She will not be available on the final day. As a result, price immediately spiked to 61,000. Ask why? Well, both autobids competes against each other immediately and final bid was 1k over user #2 max limit.
Currently, none of them will be likely to place their max bids upfront 2-3 days ahead the end of auction. Meaning that price on final day could be lower than 61,000 as both of them will be hesitant to show their intention. Other way, if final price goes above 100k then there is no advantage of having autobid. Surely, you can always amend your max level you are willing to splash.
To summarize the above, due to increased competition on auctions, you'll have to outbid more users which will be reflected in diminished value of your wallet.