IIRC there was a discussion to brought the lost coins in circulation, although it's just an idea and the developers haven't realize it.
Supply could affect Bitcoin price, but it's all about the demand, if most people not want to buy Bitcoin, it will greatly affect Bitcoin price. But, I see most people are trying to buy Bitcoin and hold it for long term, so we can say a lot of people want Bitcoin.
Bitcoin is undeniably being wanted by many people today, so bitcoin value will continue to increase overtime. The loss of Bitcoin that are yet to be realized are sometimes just something to ponder about, but if there is a way to realized them back for the owners, it may just reduce the value more if they end up selling them in the market. If the larger part of those that have lost those bitcoins gets to realize them back, and decides to hold them, there will be no changes felt in the market.