If a person dies and has some Bitcoins in a wallet with no one able to access them, his Bitcoins will remain there until someone can access them. If no one can access it, the number will remain and won't be a problem.
We must remember that Satoshi also left a very large amount of Bitcoin in his wallet and that no one has accessed or transferred to another wallet. And it doesn't affect the circulation of Bitcoin in circulation or the price of Bitcoin (probably not yet). That means the number of Bitcoins in circulation will decrease by an amount with Bitcoins that their original owners cannot access.
And that would probably make Bitcoin even more valuable as it reduces the total amount, possibly increasing the price even higher. But those are all scenarios while we are still on the Bitcoin journey and not all Bitcoins have been mined yet. That's why we don't know what will happen in the future and can only speculate.
First, I sympathize with anyone who has lost a loved one, especially if they left behind unreachable digital possessions. Its about the money, memories, and personal goals for those assets. Moving on to your Bitcoin scenario: The anticipated drop in circulating supply could raise demand if other conditions remain constant. Is Satoshi's stockpile a good example?
While a less supply may raise Bitcoin's price, other things also affect it. Regulatory actions, technological advances, and economic issues may be important. Not to be too philosophical, but it raises important concerns about digital wealth's impermanence and how society handles it. Our "Bitcoin journey" is ongoing - we're all learning, adjusting, and speculating about its future.
What you say makes sense, but we also have to see that a small amount of circulating supply can make the price rise. Likewise, what will happen to Bitcoin when the supply becomes smaller? It can increase the price of Bitcoin even though that cannot happen in a short time.
And if the supply that Satoshi has remained in his wallet and will not be used forever, the number of Bitcoins on the market will also decrease. Especially if more and more people can hold large amounts of Bitcoin in their wallets and wait for the price they want before they sell it. But it's all just speculation. We don't know what will happen in the future.
It's possible that later Satoshi will sell his Bitcoin. And if that happens, the market will be shocked and people will panic. Maybe they will also sell Bitcoin instantly because they don't want to make a loss. All scenarios remain scenarios because we don't know what will happen. And don't let ourselves be trapped by scenarios created by people.