Re: Will the need to increase BTC's max supply arise in the future?
... If at that point in time, Bitcoin's prices stay just the way they are right now (less than $1m), it may become unprofitable for miners to continue supporting the Blockchain. With no block reward, they'll be living off fees. If prices are too low, earned fees won't be able to sustain miner's operations.
Bitcoin mining is designed such that it will always be profitable to mine for some people.
By then, developers would need to raise the limit of 21 million coins to a higher value, re-introducing a block reward in order to attract miners into the Blockchain. Otherwise, the security of the Bitcoin blockchain will be at risk.
Mining is designed so that the block reward determines the level of protection from a 51% attack. If the block reward is low, then Bitcoin is vulnerable to a 51% attack. Low fees indicate that nobody uses Bitcoin, so in that case it really doesn't matter if Bitcoin is attacked because Bitcoin has already failed.
Do you think that the need to increase BTC's max supply will arise in the future? Or will Bitcoin be able to "live" just fine with a max supply of 21 million coins? Your input will be greatly appreciated. 
No. There is no benefit to increasing the limit.