Covered calls have an asymmetric risk/reward and your example depicts that. You bear all of the downside risk while having the potential for a limited profit.
AFAIC, this strategy is appropriate for a stock that you're willing to hold but have a target sell price. If taking on a new position just for the sake of the premium, AFAIC, there are safer ways to chase premium.
Writing the $55 covered call for $2 lowers your risk to $48. At $35, there's not much else to do other than let the short call expire worthless and hope for share price recovery (you should have defended the stock before it dropped that far).
If you write a $40 call, then if assigned, you'll net $40 plus the premium which will be far short of $48.
For a stock that has dropped maybe 10-20 per cent, you can use a Repair Strategy to recover losses. For every 100 shares that you own, execute a 1x2 Ratio Spread (buy one call at a lower strike and sell two calls at a higher strike. The combined position will be equivalent to a covered call and a bullish vertical call spread. All short calls are covered.