The effect of deflation is abnormal increase in price which can cause Bitcoin to be overpriced in the future. My question is what do you think will be the adoption and usage rate of Bitcoin then, whether it will increase or decrease?
According to Satoshi, "lost bitcoins are considered donations," which means they will contribute to reduced the number of bitcoin in circulation.
In such a case, the possibility of the price increasing will be high and the possibility of the price decreasing will be low; the law of demand is real.
But the question is: what will keep making people lose access to their wallets? Won't they learn how to protect their assets? And if such things keep reoccurring, do you think the common people who will want to start using bitcoin will feel safe holding it?
I guess that there is nothing any Bitcoin holder can do when they lose their coins, they have to accept the lose as a donation to the Bitcoin community, although no other holder can benefit directly from the "donation. That means that anybody that wants to hold Bitcoin must have sufficient knowledge about the importance of securing their private keys otherwise the inevitable of losing their coins permanently will happen and their only consolation is that they have donated it. I think that this is one of the major demerits of Bitcoin because aside from a holder losing his/her private keys, death, lose of memory, man made and natural disasters can also cause permanent lose because Bitcoin is not centralized, except the person shared the private keys with a trusted person or people.