P: 'Save with history'

I use History Snapshots a lot in my workflow, so this is something that I asked to be scripted, before I learned to script. Keep in mind that all History States and Snapshots are held in RAM for the open document and are not restored when opening, which is why saving a copy of the current State or Snapshot can be important.

/* https://community.adobe.com/t5/photoshop-ecosystem-discussions/save-all-history-snapshots-as-files/m-p/7857534 */
#target photoshop;  
app.bringToFront();  
main();  
function main(){  
if(!documents.length) return;  
try{  
    var Path = activeDocument.path;  
    }catch(err){  
        alert("You save your document before running this script!");  
        return;  
        }  
var doc = app.activeDocument;  
var now = doc.activeHistoryState;  
var Snaps = snapShotList();  
var outputFolder = Folder(Path + "/snapshots");  
if(!outputFolder.exists) outputFolder.create();  
for (var z in Snaps){  
    revertNamedSnapshot(Snaps[z]);  
    var saveFile = File(outputFolder + "/" + Snaps[z].toString().replace(/\./g,'_') + ".jpg");  
    //var saveFile = File(outputFolder + "/" + Snaps[z].toString().replace(/\./g,'_') + ".psd");  
    //var saveFile = File(outputFolder + "/" + Snaps[z].toString().replace(/\./g,'_') + ".tif");  

    SaveForWeb(saveFile,80);  
    //SavePSD(saveFile);  
    //SaveTIFF(saveFile);  
    }  
doc.activeHistoryState = now;  
};  
function SaveTIFF(saveFile){  
tiffSaveOptions = new TiffSaveOptions();   
tiffSaveOptions.embedColorProfile = true;  
tiffSaveOptions.byteOrder = ByteOrder.IBM;  
tiffSaveOptions.transparency=true;  
tiffSaveOptions.interleaveChannels=true;  
tiffSaveOptions.alphaChannels = false;   
tiffSaveOptions.imageCompression = TIFFEncoding.NONE;   
activeDocument.saveAs(saveFile, tiffSaveOptions, true, Extension.LOWERCASE);   
};  
function SavePSD(saveFile){   
psdSaveOptions = new PhotoshopSaveOptions();   
psdSaveOptions.embedColorProfile = true;   
psdSaveOptions.alphaChannels = true;    
psdSaveOptions.layers = true;
psdSaveOptions.annotations = true;
psdSaveOptions.spotColors = true;
activeDocument.saveAs(saveFile, psdSaveOptions, true, Extension.LOWERCASE);   
};  
function SaveForWeb(saveFile,jpegQuality) {  
var sfwOptions = new ExportOptionsSaveForWeb();   
   sfwOptions.format = SaveDocumentType.JPEG;   
   sfwOptions.includeProfile = false;   
   sfwOptions.interlaced = 0;   
   sfwOptions.optimized = true;   
   sfwOptions.quality = jpegQuality;  
activeDocument.exportDocument(saveFile, ExportType.SAVEFORWEB, sfwOptions);  
};  
function snapShotList(){  
var doc = app.activeDocument;  
var hs = doc.historyStates;  
var now = doc.activeHistoryState;  
var Name = new Array();  
for(var a =0;a <hs.length;a++){  
   if(hs[a].snapshot) {  
       doc.activeHistoryState = hs[a];  
       Name.push(hs[a].name);  
       }  
    }  
doc.activeHistoryState = now;  
return Name;  
};  
function revertNamedSnapshot(name) {  
var desc = new ActionDescriptor();  
var ref = new ActionReference();  
ref.putName( charIDToTypeID('SnpS'), name );  
desc.putReference( charIDToTypeID('null'), ref );  
executeAction( charIDToTypeID('slct'), desc, DialogModes.NO );  
};  

“Adobe could simply have Photoshop rerun the commands when the file opens if said user opts for that annoyance.”

This could (mostly) be done with an action recording every move, with the option to record brush strokes. I personally wouldn’t want to go there!