I made the same realization in myself, but unfortunately in my 30s rather than my 20s. Engineering, whether software or hardware, is all about thoroughly understanding a problem and dissecting it to the nth degree. The better you are at this, the quicker you notice the problems with an initial, creative idea.

"It's easy to be a critic."

If left unchecked, all that is done is the refinement of a skill that is able to find the potential hurdles/blockers in any problem space.

However, when part of a balanced team this attribute can save time going down dead-end paths. But it requires a yin to the yang - a perpetual optimist that won't take no for an answer.

For those of us that are on the analytical end of the spectrum, it is important to realize that noticing an early issue does not equate to the problem space being a waste of time that is unsolvable.1 Instead, use your super-power for good to accelerate finding the efficienct solution to the problem that some has identified and clearly expressed (which is itself itself a super power; and you may have just found your startup founder).