No strong feelings about it one way or the other. But I have a few comments:

1. If you're going to shuffle the primary schedule, they should all be moved many months closer to the election. Maybe June and July can be the primaries, with conventions and the general election starting in August as we do today. No one benefits from such a long election season. In 2020 the primaries were decided before the pandemic was on the average person's radar, and of course the pandemic was probably the biggest issue during the general campaign. The issues discussed during the primaries would have been very different if the elections were held in June and July.
2. Call me a cynic, but in 2020 Biden lost in Iowa and lost in NH then won in SC. If he's planning to run again and thinks there could be competition in the primary, it seems very much to his benefit if SC moves ahead in the calendar.
3. Again, maybe I'm a cynic, but in 2020 Biden got the endorsement of prominent South Carolinian Jim Clyburn prior to the SC primary. The media credits this endorsement for Biden's performance in the SC primary. (The April 1, 2020 Washington Post headline is "Jim Clyburn changed everything for Joe Biden’s campaign" and the article notes "Sixty percent of black voters cited the Clyburn endorsement as an important factor in their decision.") One wonders if there was some backroom deal struck: I'll endorse if you work to rearrange the primary schedule in SC's favor.
4. In 2020 Biden lost the first two states, won the third, and obviously went on to win the nomination. The media loves to talk about the first votes cast, but are we sure they matter that much?