Why does the halving event take place every 4 years? So, as per my understanding - bitcoin halving takes place when 210,000 blocks are mined. And blocks contain transactions - and they contain the same number of transactions (more or less). So, as the popularity of bitcoin keeps on increasing, wouldn't more transactions take place daily?
And if that is the case, then more and more blocks would be mined every day. And bitcoin halving event would take place faster and faster.
The only way bitcoin halving event takes place around the same time every year would be if every block is holding more and more information as time goes.
What do you think? I am so confused.
as the popularity of bitcoin keeps on increasing, wouldn't more transactions take place daily?

Yes, scaling of Bitcoin is a recognised issue. For people who use Bitcoin as a currency, as its creators intended, the solution is mostly off-chain payment systems such as the Lightning network. For speculators and day traders who treat Bitcoin as nothing other than a speculative asset, the solution is off-chain trading on exchanges. It seems one likely outcome is that use of the blockchain will gradually shift to being mostly closing settlement of off-chain systems.

more and more blocks would be mined every day

Bitcoin code attempts to keep the rate of new blocks at a constant rate of one every 10 minutes. It does this by periodically adjusting the mining difficulty.
In practice the interval can vary greatly from block to block but over a long period the average is close to 10 minutes. Usually it is somewhat less and in some years significantly less. I think in 2010 it may have averaged around 7-8 minutes from memory. Nevertheless, the rate is moderated and doesn't increase in an unbounded way.
See What keeps the average block time at 10 minutes?

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