Many people bought storage during this wave, but sold too early.

Regretting not using it, blaming yourself is also useless.
First, clarify one thing: did you sell because "it rose too much and you're afraid of a pullback," or because "you never really thought about when to sell"?
The former is normal; you need to review and learn to sell in parts, not go all-in at once.
The latter is the most fatal; you didn't think it through on the day of entry, and selling prematurely is just the result, not the cause.
Holding a stock, the core logic is only one thing: whether the reason to buy it still exists.
What is the logic behind storage, there's no need to say more; as long as this logic hasn't changed, it's not time to sell.
If you're still in the car, hold on.
If you've already gotten off, don't worry about the money you didn't make; I believe storage isn't over, and a pullback is still an opportunity to get back in, but don't listen to people saying go all-in or buy blindly.
Selling too early isn't the worst; the worst is selling prematurely and still not knowing why you sold.