I suspect that if the US can rebuild bombed out Britain, that the Messiah can restore whatever He feels like restoring. He can improve whatever He feels like improving.
I expect there'll be a lot of improving going on.
Spiritual does not mean symbolic or allegorical.
God is Spirit and those who worship Him must worship Him in Spirit and in Truth.
Should I suppose that in your theology that God is a mere simile, metaphor, symbol, or allegory?
Are you saying that restoring the Temple, which has no purpose in the Christian age, might be something that Christ seeks to do?
No, but God certainly represents Himself to men in terms of symbols. He uses symbols, metaphors, etc all over the place in Scripture. Certainly you are not denying this.
For example, the dove that appeared in Matt. 3:16, was that "literally" the Holy Spirit, or was it a representation of the Holy Spirit to accommodate our human senses? Easton's says, "It is a symbol of the Holy Spirit."
The tabernacle on earth ... what did that really represent (Heb. 8:5)?
What did circumcision of the foreskin symbolize (Col. 4:11)?
Prophecy is full of signs and symbols. “The Revelation of Jesus Christ, which God gave Him to show His servants--things which must shortly take place. And He sent and signified it by His angel to His servant John,” (Rev. 1:1)
There nothing wrong with spiritualizing or understand the spiritual meaning found in the Bible. In fact it is impossible to make any sense of the Bible without doing of good deal of spiritualizing. Can it be abused? Absolutely, just read Scofield’s Notes to see some terrible abuses of symbols, typology, etc.
The error that some folks believe is that “symbolic” or “spiritual” interpretation is not real interpretation. Nothing could be further from the truth. The Jews of Jesus day got into trouble over the person of Messiah precisely because they could not understand the spiritual nature of the Kingdom of God. They were too literal. Jesus explained the true spiritual meaning of all the OT prophecies and how they applied to Himself. Some got it and some didn’t. Like the folks in John 6 who could not deal with these words, “I say to you, unless you eat the flesh of the Son of Man and drink His blood, you have no life in you.”
Only those with spiritual eyes who understand the symbolism will get it.
But if you call yourself a Christian you understand the need for spiritual eyes, and recognizing the symbolism for what it is, a pointer to the great God and Savior, Jesus Christ.