In my opinion, they should not. In my experience training, the fence benefits strikers just as much as it does grapplers. Getting takedowns against the fence are incredibly different than open mat takedowns and a very stiff challenge in many scenarios (in other scenarios, takedowns are a little easier against the cage).
I feel that there are already enough rulesets that are anti-wrestling as it is -- every fight starts on the feet and at a distance. If you clinch with someone and don't work hard enough, the fight is separated. If there is no action between fighters while standing and separated, the referee doesn't have the fighters clinch.
If you take a fighter down and don't do enough work, the fighter on bottom is rewarded with a fresh start on the feet. Referees oftentimes even do this when the person on top is being active.
When the round ends with a fighter on bottom, they get rewarded by starting the next round from standing. This is a huge advantage for strikers with poor abilities to stand up.
I get why these rules exist fyi -- if fighters were allowed to clinch against the cage or lay on their opponents without doing anything for 15 minutes, the sport would not strive and grow in a way that allows MMA to prosper. Restarting fights in new positions when the fights have no activity is a necessary evil for the growth and success of the sport. However, I'd say that strikers have enough advantages as it is and do not need any further handicap against grapplers.