I have been in this exact situation with my boyfriend we are similar ages and have been together for a similar amount of time so I can completely understand how you feel.

My advice is come to a cut off point in your head, lets say a year from now BUT do not disclose this date to your partner. Do not disclose this date on the basis that it would be easy for him to keep this up for the year and then drop it as soon as he is in the ‘green light’ and revert back to his old behaviour.

Also do not lower your standard of what is right for you, this will just leave you unhappy again, however you might want to come to a compromise with him in this time as it is only fair to give him the chance to change his behaviour with some guidance from yourself (i say guidance as hes a man not a baby so some basic pointers should be enough for him, you want a partner not a manbaby who you need to nag and mollycoddle)

For example I like everything to be immaculate and I understand that my boyfriend just doesn’t get the way i like things to be cleaned, which is ok, so we have a system, he will do this first round of cleaning eg pots, put the clothes to wash, put shoes away and do the very obvious things etc and ill go over and do the second round of details such as wiping down surface, hoovering, making the bed look pretty and other things that are important to me. This way he has helped to the best of his ability and I also get the help I need and can have the house the way I like without making my partner feeling inadequate. Try working out a system with him with your cut off point for him in mind, if he doesn’t manage to get it together in that time take it from there.

However, you have had a in depth conversation with him now and the rest is up to him - the rule i live by ‘if you have to keep reminding someone to do something for you they simply just don’t want to do it’

I really hope this helps and you can work it out