e4 Vs d4

Everyone learns e4 as a beginner.  And their play evolves around defending against that when playing black. 

So d4 is better against players with lower averages.  

The question is rather like: Should I go to college or try to start a business? Well, it's up to you and it will determine the outcome of your life, but there is no one answer that is better or right to the question.  What kind of game do you want? What are your strengths?

Openings in which experience trumps theory are better at lower levels than extremely theory-dense, complex openings. Up until you hit about 1600, I wouldn't recommend focusing on the four most popular openings: the Ruy Lopez, Sicilian, Queen's Gambit + variations, and Indian Game + variations. I would instead recommend playing simpler openings. For players who hate theory openings or are under 1000: Alekhine's, QID/KID, Scotch, and Reti are all solid, extremely simple options to learn. For those who are ambivalent to theory openings or under 1300, the Pirc, Vienna, London, and Caro-Kann are relatively simple to play but have a hidden depth. For those who really enjoy theory openings or are under 1600. The French, English, Petrov, and Italian all have incredible depth and theoretical variations while not being as complex. Here are my reasons why the four most popular openings are unreliable at lower levels.

If I somehow have Grandmaster prep in the Sicilian, I've memorized every Sicilian variation out to its full completion of theory as white or as black and know all of the ideas, and have spent all my time playing chess playing the Sicilian, I am lost immediately if 1. d4 or 1... e5. If I focus on and memorize the Ruy Lopez to the same extent, I am lost immediately if 1. d4 or 1... c5. If I focus on and memorize the Queen's Gambit, Slav, and Semislav in the same fashion, I am lost immediately if 1. e4 or 1... Nf6. If I focus on all of the variations of the Indian the same way, I am lost immediately if 1. e4 or 1... d4. Hopefully my point is clear. Focusing on one opening to such an extent is actually detrimental to your success as a lower level chess player, as any move which breaks your opening prep (and isn't a blunder) will win your opponent the game. Even if someone does play the "correct" moves into your opening, they might still play a line you are unfamiliar with (Bird's Defense against Ruy Lopez, Alapin Variation against Sicilian, QGA against Queen's Gambit, London System against Indian), in which case you will probably lose, as your opponent most likely knows the theory if they have it prepared against your opening, and most likely has experience with it, as it's an extremely popular opening.

However, if you instead memorize anywhere from 2-8 offbeat or hypermodern openings as white and 2-8 offbeat or hypermodern responses as black with more focus on quick, immediate imbalance such as gambits and games (for aggressive players) or slow, positional fortification such as defenses and systems (for defensive players), you will have answers for everything and the only times you will be unprepared is against players who play EVEN MORE offbeat openings than yours, in which case you might have a chance due to openings that obscure usually being disproven or overall losing. I would recommend knowing at least one line in the popular openings just in case it gets played against you somehow and as practice for once you have enough experience and ELO to play the opening, but I'd make the same recommendations as previously. Pick a relatively simple line, especially gambits or heavily defensive variations (Jaenisch for Ruy Lopez, Slav Exchange Variation for Queen’s Gambit, QID for Indian Game, Smith-Morra Gambit for Sicilian).

tl;dr 1. e4 and 1. d4 are both fine, just as long as you are aware of your strengths and weaknesses and prepare openings accordingly. If you are lower ELO/don't like theory/can't memorize openings easily, don't play theory. Make sure you have a wide repertoire. Don't focus on Ruy Lopez, Sicilian, Queen's Gambit, or Indian until 1600.

e4 is better

e4 opens up two diagonal pieces

d4 opens up one

Also check the analysis and allow engines. You can see that e4 is a bit higher than d4

Very true. Also, there are many gambits and traps that some from e4.