Unfortunately, the answer to this question would be, no, he did not. Zenitsu, along with Tanjiro and Inosuke got way stronger than average corps members with training. In fact, he became one of the very few to even invent a new form of Thunder Breathing. However, his dream of becoming a Hashira was never realized.
At this point Zenitsu has manifested his speed and power, and he was also able to keep up with the Demon King, Muzan, even when weakened. It's possible to say that his power easily matched the strength of a Hashira.
Tanjiro, Zenitsu, and Inosuke didn't become Hashira since they aren't ranked Kinoe, one of the requirements to become a Hashira. This's confirmed in Rengoku: Gaiden.
While awake, his nerves and fear cause him to freeze up so he cannot move. When his life is in danger, his nerves and fear grow so strong that he passes out. But while asleep, his nerves are no longer holding him back, allowing him to fight and move with great judgement, precision and skill.
Overall, Zenitsu is an extraordinary powerful Demon Slayer capable of singlehandedly bringing down an Upper Rank, which said to be able to overpower 5 Hashira, in 10 minutes, albeit he would have beheaded Kaigaku in a heartbeat if it wasn't for his feelings of melancholy and pity.
1) Inosuke Hashibira
Although Inosuke possesses immense strength and endurance, he's no match for Zenitsu's insane speed and his Thunder Breathing.
Demon Slayers are known for their strength and bravery in battle, but not Zenitsu. Despite his cowardice, he's one of the strongest in the series.
Thunder Clap and Flash—Godspeed is the most powerful of Zenitsu's derivations of the Thunder Breathing first-form technique.
Given how talented Tanjiro is, it's likely he'd defeat Zenitsu, even if the latter could fall asleep and call on his powers. Tanjiro's demonstrated his ability to take down more powerful demons and adapt to training on more than one occasion, so it just makes sense.
Superhuman Hearing: Zenitsu has always had enhanced hearing, being able to hear what others can't. He is able to hear a faint difference that is normally indetectable to humans in the sound of a moving human and a moving demon. His hearing gives him extra awareness for danger.
Demon Slayer fans know Jigoro Kuwajima as Zenitsu's master. But there's much more to the former Thunder Hashira.
2 Sanemi Shinazugawa, The Wind Hashira.
Master Swordswoman: As a member of the Hashira, Nezuko is one of the most powerful and skilled sword-users in the entire organization. Nezuko is a highly skilled master-level swordswoman, having been trained since birth to be able to defend herself using a katana.
Gyomei Himejima, the Stone Hashira, is the strongest Hashira in the Demon Slayer corps in terms of strength and swordsmanship. He is the only person who uses spiked flails and an axe instead of standard swords to kill demons.
3) Zenitsu Agatsuma
If he could, Rengoku would win simply because Zenitsu cannot perform Godspeed more than twice. Since Zenitsu only knows the first form, Rengoku would know what to expect and accordingly counter his moves, taking him down in the end.
2) Tanjiro Kamado
With Sun Breathing, which is regarded as the paramount of all Breathing Styles, Zenitsu will have a hard time subduing Tanjiro and will be defeated by the latter in no time.
slow ?! , Deku was able to dodge and hit in a split second. And yet he is clearly faster than Zenitsu .
Fighting Style
During the events within the Infinity Castle, Inosuke has undeniably polished his swordsmanship skill to the level of a Hashira, allowing him to keep up and go toe-to-toe with Upper Rank Two, Doma.
Initially, Tanjiro's accuracy and strength were not up to the mark, which is why Muzan was able to avoid his attacks. However, Tanjiro accurately performed the thirteenth form and inflicted a ton of damage on the Demon King.
Among the current generation members, Shinobu and Zenitsu are the fastest characters in the series. According to the Upper Moon 2, Shinobu was the fastest opponent he had faced and was unable to react to her attacks due to its speed.
NO. It's his subconscious mind that helps him fight. When he fainted out, his subconscious mind takes over( something like semi-hypnotic state) and unleashes the lighting breathing. Consciously he is not confident enough.
Currently, it's Zenitsu, when he activates his 7th form. It was so fast that an Upper Moon could not even see what he did; the upper moon he killed. The second would probably be Shinobu, She is said to be the fastest Hashira, but the weakest, because of her size.
Despite her petite appearance, Mitsuri Kanroji has a special muscular composition that makes her muscles eight times denser than an ordinary human's. She is also more flexible than the other Hashira. These two strengths balance out her being the slowest runner out of all the Hashira.
Thunder Breathing is one such technique that Zenitsu has used to great effect in the series. Of course, Zenitsu is only the master of the first form, but it goes without saying that the other techniques of Thunder Breathing will also be awe-inspiring to witness in Demon Slayer.
Yoriichi Tsugikuni was the first Demon Slayer and also the one who invented Breathing Techniques in the first place. Yoriichi was born with the Demon Slayer mark and prowess in swordsmanship. His powers were beyond comparison as he defeated Muzan once and had him on the verge of death until he managed to escape.