No. Top speed is limited by available horsepower, which doesn't change with what gear you are in.
Gearing allows you to keep the engine close to its best operating speed at the different road speeds it will encounter from just faster than stopped all the way up to its maximum operating speed. But the highest gear is typically chosen so that maximum engine power coincides with the speed at which total power required by drag is equalled.
A higher gear than that would make the engine run slower and produce less power than it was producing in the old top gear and so the car would slow down. Some cars actually have their highest gear setup like that so that the engine will be turning slower at highway speeds.
All more gears would do for you is keep the engine closer to maximum power as you accelerate, letting you get to top speed a little faster; at least until you have so many gears that the time spent out of gear while changing eats up all the advantage you've gained.
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