Not relevant. We are talking about Bitcoin as a transaction system and a store of value. The blocksize limit is a different issue.
Although different, it is closely related. To raise the blocksize limit, you have to do a hard fork, and a hard fork might affect "store of value" property of bitcoin
A hard fork means there is a change in bitcoin protocol, that will shake people's belief on many claims of bitcoin, just like OP wondered, technically speak, all of bitcoin's claims can be changed with a client upgrade, then who is going to guarantee the consistency? This "Hard Currency" start to feel soft
If a hard fork will never happen, then "store of value" property will be intact. But this transaction system will become slow and expensive over time due to the block size limit, it might not be very practical to use bitcoin, when you need to wait for days/weeks for a confirmation (if you don't want to pay very high fee)
What is your view on this?
My view is that the association is silly. The max_blocksize rule was added by Satoshi after the system was already running, in order to remove an attack vector via spamming of the transaction queue, until such time as a more elegant solution could be found. It was never even intended to be a permanent rule. The only reason that a "hard fork" might be required to raise or remove that rule is if some people don't agree that we should raise the limit. Complete consensus is required to avoid a hard fork, and a hard fork is the last argument of otherwise independent bitcoin users. Forcing a hard fork in order to alter some aspect of the network doesn't even mean that you'll succeed in altering your desired aspect, but the resources required to fight the good hard fork fight are quite high, and completely unrecoverable. Yet, if a minority of users and miners decide to make that fight, there will be a blockchain fork, and the majority of the losses will fall upon the minority group until they can either muster up the resources to dominate the network or quit the fight and take their balls and go home. So, theoretically, all that is needed to change the 21 M BTC limit is to get everyone to agree to that change; but that isn't something that is up for debate here. No matter who or why, there is no way that a consensus to change that metric in Bitcoin is going to happen without a blockchain fork; and it would be a harsh fight. That number isn't so arbitrary, unlike the max_blocksize rule.