So i thought i'd take a look at a bit longer term monthly chart on the SPX.
As you can see here, for the past 10 years or so, after having broken above the '07 top resistence level at around 1550
SPX has had a 2-3 year stretch of three runs, followed by respite and or corrections.
And at each of these times, you can also see that the 50MA served very well as a rally support for the next "run".
Now, there's nothing that says one MUST kiss the 50MA, which would be right around a fib support of ~ 3470 or so,
but if SPX would take a negative turn down from current levels, then we may expect this level to be support once again
as it has proven to be in the past.
It may also overshoot as it did back in March of 2020, that gave everyone a scare. If that were to happen again, next support
from that level would be 3200 or so.
Keep in mind that past results do not predict future outcomes... just a consideration when looking at things long term while in
short term volatility. :)
Good luck.