Lots of variables: Market size, format, heritage of existing talent, and profitability of live programming.
If you have a top-rated local morning show that's making tons of money, you have nothing to worry about. If you're ranked #13 in a 14 station market, then an option is syndication. Keep in mind that the money you save in salaries and benefits is lost in local avails. Then again, if you're #13 in a 14 station market, that's not a problem, because you have lots of unsold avails.
What killed local hosts after 7 PM was the huge audience drop-off. It's been a problem for 25 years, and now there are some very good choices. For some stations, it's a problem in other dayparts. It gets back to the fact that there are too many radio stations in some markets to support local hosts.
Here's another reality: If you're a low rated local show, you are probably finding it hard to book quality guests. The syndicated shows have larger audiences, so they can deliver top stars. Doing local radio needs to be more than simply having a local body in a chair.