Do men get turned on by regular pictures???

Apologies if this is too sexual or a strange question. Ive been on reddit more and realize there are So so many thirsty men on here and SOOO much nsfw content. Usually the NSFW content im seeing is pics. And sometimes the pics dont even have to be provactive, but if the woman is busty or has a nice ass or even just a nice face there are men simping in the comments. And im wondering if these pics alone, get these men turned on and hard??? How is that possible? 😭😭😭

Yes of course erections are involuntarily controlled, but how are pics alone enough to get them horny and harassing women in their DMs. Im wondering…….