JavaScript Redirects - Are They Still Bad For SEO?

So I have a client that is based strongly on JavaScript.

They have now implemented JavaScript redirects, I know this type of redirect used to be a no-no.
But Google has confirmed they follow them similarly to usual redirects in a recent Q&A

I am dubious to believe this and concerned that although it should work, the reliability is lower and not worth the risk, especially for important pages.


My main concerns are:

• Putting trust in something that is supposed to work vs something that will definitely work (301 redirect)
  
  
• Although supported by Google, other search engines might not support them.
  
  
• JavaScript is crawled less frequently by Google
  
  
• They might not pass 100% of the same PageRank
  
  
• Harder to detect issues with and detect redirect chains especially those that lead to 404s.

What are your guy's thoughts on this?

It's just like you said, not all indexers / crawlers support running javascript, so a redirect link might still get indexed in other search engines or cause conflict. On the other hand if you're heavily depending on js through libraries like react or vue, through server-side rendering it should generally not be a problem.

Clientside redirects are bad in my opinion, i handle redirects on the serverside and have custom rules for how to deal with crawlers and robots otherwise it'd have neg effets

No, they are not the same and never will. 3** redirects are sent as an HTTP response, whereas all in-browser redirects are the result of a 200 (OK) HTTP response. A 300 response code tells the client that the resource is not found at the requested URL, a 200 response code tells the client that the resource was found in the requested url.