Memecoins bring a lot of new people into crypto because they are simple, viral and sometimes can make huge profits fast. but at the same time they also increase scams rug pulls and pure gambling behavior in the market. some people enter crypto because of memecoins and later start learning about Bitcoin and blockchain. others lose money quickly and leave with a bad image of the whole crypto space
To answer your question straight I will say that memecoins harms the crypto market reputation very much just like any experienced person in the crypto market will tell you. Bitcoin is very popular and many people have heard about the stories of early buyers who have become very rich today as a result of successive ATH in bull seasons. When they hear about a memecoin hype on social media they will think that the project is just like Bitcoin that they have been hearing about.
Without making research about memecoins they will put a lot of money into it with the believe that within a short time that they will gain a lot of profit as they were told but in the end the project will die, they will lose all their money and they will blame cryptocurrency that it is a scam. Information is power and those that don't understand that memecoins are gambles will keep losing money and giving the crypto market a bad name.