Yes, your parents could name multiple executors, but sometimes quick decisions have to be made, 2 or 3 executors can be cumbersome and only 2 can produce a stalemate. And for most modest estates multiple executors is not necessary or wise.
Despite what some people think, it really is not an HONOR to be named executor, it is a burden, often a thankless one that gets the executor criticised for perceived slights or claimed unfairness. Remember as a kid one child would cut a pie or something in half and the other had a chioce of which half to avoid unfairness (real or imagined)? Here one has to cut and take what the other chooses.
It may make sense for your parents to explain why they named you to your siblings to avoid the "you always loved him more" situation. If they explain it was not because "we love or trust him more than you" but instead was for a good reason, that should calm sore feelings. It likely was for a good reason. Perhaps it may have been based on distance, greater business or negotiating experience, assumed time available, familiarity with aspects of the property, etc. rather than a distrust of dislike of the other or their spouse. Or, maybe they felt she was named for 10 years and now you'll be named for the next 10, and then they'll revise things again, etc.
Regardless of who is "it" when the timne comes, it usually is wise for one sibling to consult with and take the siblings into the decision making process, particuarly when it comes to "cutting the pie", or deciding to sell something of value, etc. Giving others opportunity for input "when the time comes" often leads to better decisions and appreciation for the burden.
