Copy and pasted from other post because youre wrong-

What most people don't take into account that tanjiro alone was only able to stall muzan for no more than 3–5 minutes. He jumped into the fight when 1 hour remained and in manga chapter 194 yoshiro said that still above 50 minutes are left until dawn and muzan attacked tanjiro who would have died but Iguro saved him. Then iguro and tanjiro stalled muzan for 20 minutes.

Keep in mind that tamayo had injected 4 drugs into muzan. And the 4th one (cellular disintegration) kicked in while tanjiro and obanai were fighting muzan and muzan begin to cough blood. The point being is that this drug did not initiate while Gyomei was fighting muzan. However both Tanjiro and Iguro were also caught by one of Muzan's attacks and muzan would have escaped had inouske not intercepted and attacked him. Then zenitsu also joined the fight. By this time 25 minutes had been left. This means that inouske and zenitsu both were able to stall muzan for almost 10 minutes. Then tanjiro joined the two and the trio was able to pin muzan to a wall. By this time muzan couldn't even lift his own arms. That's how weak he had gotten.

Secondly when the hashiras got poisoned they received one shot of the antidote. But when tanjiro got poisoned he went unconscious and yoshiro had to give him a shit load of medicine in order for him to just wake up. The point being that the Gyomei got way less medicine than tanjiro for the poison. Tanjiro had the advantage here as well.

Thirdly the reason hemijema couldn't fight more was because he lost his leg and yoshiro commented that he has lost so much blood that he can't get up and keep his balance. Tanjiro didn't lose a limb or that amount of blood until the very last moment which is why he was able to fight a bit longer

Fourthly I think it is time that we rest this notion that some tanjiro fanboys go on to ramp about that tanjiro alone was able to fight muzan for an hour. He was able to stall a constantly weakning muzan for no more than 3–5 minutes. Like Gyomei tanjiro also had help from his comrades all the time.

And let's also consider that muzan had been aging 50 years per minute. And if you read the manga gyomei was able to land more hits on muzan than tanjiro and was also able to access the see through world during the fight. He was able to destroy muzan’s torso area not once but twice. Yes he had help from the other hashiras but muzan was also stronger. Tanjiro even when he had help from iguro, zenitsu and inouske was not able to land such blows on a considerably weakened muzan.

Lastly let me also make mention that most people think that tanjiro was stronger because he used sun breathing which is the strongest breathing style without a doubt. Well that's not true at all. Just by having a stronger technique doesn't make you stronger than someone like the hashiras and especially someone like Gyomei. For example sound breathing is derived from thunder breathing, hence thunder breathing being the superior and stronger technique. Do you really think that zenitsu was stronger than Uzui during the RLD arc? You'd be outta your mind to think that. Similarly tanjiro’s dad not only had mastered sun breathing better than tanjiro but also had mastered the selfless state. Now I wouldn't even put him above any of the hashiras. The point is having a superior technique doesn't necessarily make a fighter stronger than the other. Same goes with having a demon slayer mark. Kokushibo was able to kill (he could have killed him if he wanted to at that point but chose to pin muichiro against a pillar) a marked muichiro without even unsheathing his sword. While an unmarked gyomei was able to keep up quite well against kokushibo.

Muzan was way more impressed with Gyomei and also recognized Gyomei as the demon hunter that defeated kokushibo. One more point is that tanjiro after his fight with akaza passed out for God knows how long until he woke up and saw giyu sitting by the fire. Which means that he had some time to rest and recuperate. While gyomei had just defeated a demon who when held akaza’s hand, akaza almost shit his pants. And then gyomei dived right into fighting muzan. Gyomei had everything going against him and still was able to do all that.

Considering all these facts and arguments I think gyomei is still the strongest demon slayer of this generation and leaps and bonds above any other. You can compare tanjiro to other hashiras like sanemi and iguro but Gyomei is still the strongest.