For years people thought, probably correctly that DST vs Standard time was basically established for farmers coupled with the arrive of sunset and/or sunset and how that affected their work hours (chores) and the milking cycles for dairy production. As far as growing time it is the same no matter what time you place on the beginning or the end. Daylight will have the same duration.
Then things like time zones existed again for a reasonable lining up with, again, sunrise and sunset, but, the reason that it is important to have standard areas was for the purpose of scheduling transportation after the railroad extended across the nation and arrival times and departure times would be consistant within the confines of the mapped out areas. Again based on sunrise and sunset.
Many people feel that using DST expands the amount of daylight. It does not, it just changes what hours that daylight exists in. All that said I don't think that it makes all that much difference except that everyone within any designated area cannot have their own time zone. That would cause massive confusion, missed appointments, etc. I think Arizona does not do DST, but, that is one place and has little impact on anything. Hawaii is a separate area all by itself and any of the water mass between one land mass and another is of no concern because no one lives there, except maybe Sponge Bob Square Pants and his pet snail Gary.
Personally, I'd like to see DST abolished completely and some other way be created to remember when to put new batteries in our smoke alarms. In this day of rapid transit it is just something else the we have to remember to do and then take half the time that it lasts to adjust our bodies to that difference in time. Or if everyone likes later daylight the just make DST the new standard time. Then, of course the whole world needs to change.