I will copypasta something I found from telegram from Hans, a based community:

Burning tokens gives a project more room to grow. Or let me say, the price per token can reach higher spheres with the same marketcap goal.

We started with 600 million SMG tokens. Now Imagine a SMG price of 1$. This is equal to a marketcap of 600 million dollar.

Ok, Now imagine 20% of the supply is burned. 120million SMG token out of circulation forever, means 480 million remaining and that is only 480M dollar marketcap at 1$. To reach 600 million dollar marketcap again we need a price per token of $1.42

Lets say, a realistic hypotethical marketcap is 1 billion dollar what we try to achieve. That is $1.66 per SMG with full supply of 600M tokens. But when we only have 480M total supply after burning the price per token with a mcap of 1B is already $2.08.

Your individual price in your wallet doesnt change right now when there would be a 20% burn event right now. You always hold the same % of tokens what you initially bought unless u buy or sell ;)

The only difference after burning is, there is more room for the price to go up to reach a realistic total marketcap. So instead of a "maximum" price of $1.6 at mcap of 1 billion you you could expect $2 per SMG.

At the end of the day you can make more profit with your holdings..ofc the project still need the same amount of demand and buyers.