kinda? Sort of the same applies to kokushibo. It wasn't until he saw his own wretched reflection that he lost his will to live and the damage he had taken actually affected him. In the end, without sunlight sufficiently advanced demons just can't be killed by any means that we know off.Off topic Muzan would have win this war and Become complete immortal, had Akaza didn t kill himself. Its too bad for Muzan. Thanks god Akaza kill himself. This war would been logically Muzan victory If Akaza didn t kill himself.
Him trying to Turn Tanjiro is out of desperation and kinda stupid but he didn t have choice. He should known Tanjiro wouldn t want to live forever and become invincible its was never in Tanjiro character to be like that.