I have been working as a web developer for several years, fixing issues, errors, and increasing page load speed etc. but I'm kinda new to SEO and Google Search Console.
I have a client who is using Laravel and due to his disorganized use of the routes and mistakes in link rewriting rules in Nginx config the website has ended up with thousands of wrong links indexed. I'm talking about 20,000 links.
So the client wants to redirect all those links to the correct content and keep them in the Google index so that the website ranking doesn't go down, but I don't think this is the best approach.
My question is whether removing this large amount of incorrect links will greatly affect to the website ranking/SEO negatively?