As someone who comes from a country where we do require photo ID for voting, not requiring one feels absurd, so I asked the same question. Apparently in the US, there is a part of the population that doesn’t normally get photo ID and that part is mostly poor people and minorities and photo ID laws are used as means of disenfranchisement, similar to having the voting days during business days (when many people can’t come to vote) or having voting stations far away in an area with limited public transport options.
Where I live in Finland, the police will actually grant you a temporary photo ID only for voting if you don’t have one, although most people have passports. There are early voting stations in basically every post office for a week and the main voting day is always on a Sunday. No excuse to miss voting.
I’ve only missed one voting during my life, at a time when I was living in another country and there was no consulate in the part of the country I was in. Nowadays there’s also the option of mail-in voting when outside the country, I don’t know if it wasn’t a thing back then or I just didn’t know.
That’s not to say I didn’t want some improvements in our system: I’d like to see ranked choice voting or something similar here, there are some smaller parties I’ve been voting and it seems they seldom have a chance.