Does the Taproot update benefit all bitcoin users? or is it for a selective amount of people I came across a blog post where it mentions that the taproot update is promised to speed up BTC transactions, lower their fees, etc. but does this mean that literally, anyone sending or receiving BTC will benefit from it? will it require special software to operate?
Bitcoin transactions require a certain size and with taproot and tapscript we can decrease that size.
This means that effectively we will be able to store more transactions in one block allowing overall a slightly higher throughput of bitcoin transactions in the network.
So even if you continue to use legacy transaction formats you might still benefit from the fact that the blockchain might be less congested as it can fulfill a higher demand with the same space.
Of course if you want to use it you will need a wallet / software that supports the new format but as it seems it will be merged to bitcoin so modern wallets should be compatible and also implement it.
The only direct benefit that you get from switching to taproot is that your tx will be smaller in size allowing you to either save on fees or if you want to pay the same fees allow you to have a higher feerate. Though miners are not forced to mine transactions with highest fee rates first they are certainly economically incentivized to do so. Thus besides doing something good for the network your tx might also be confirmed faster.