Does this really affect the market value of the coins?
It does, it brings impacts to a coin value. There are already many developers burning their coins, then the price of the coins can increase instantly in the market. In theory, burning means decreasing the total supply. It makes the number of coins become less than before. In this situation, the price of the coin can be higher since the number of the coin be more limited than before. You must know the economic principle, right? When the stuff becomes rare, the value to be more expensive.
Good projects should indeed have a limited supply and a burning coins plan must be carried out, in order to make the value of the coins increase.
Therefore, usually if there are projects that provide a schedule for burning coins, investors will immediately buy the coins, because usually the price
will rise instantly and this is an opportunity to make a profit. This method of burning coins is done by developers to attract investors, and has proven
to be effective. But it depends on the project too, if shitcoins are planning to burn their coins, it still doesn't make the shitcoins worth buying.
So we as investors still have to do research and analysis to choose coins that are suitable for investment.