1. Question: Why is the blessing Kiddish Levana considered a time bound mitzvah which women are exempt from but the blessing of shehecheyanu on a new fruit is not (See Magen Avraham in the name of the Shelah Shulchan Aruch Orach Chaim 426:1)
A. The Chochmas Shlomo there actually argues and holds Kiddush Levana is not time bound because only mitzvos that could technically be done all year around, at all times like shofar, Sukkah, tefillin, tzitzis etc. but the Torah gives them a specific time to fulfill the mitzvos are considered time bound but kiddush Levana is dependent on the cycle of the moon, it can’t be said on the second half of the month because it is waning then and the Rabbis enacted it should only be said when it is waxing, so you can’t technically say it whenever you want like all other time bound mitzvos.
B. Kiddush Levana which is based on the waning and waxing of the moon sounds like a similar concept as saying a shehecheyanu on a new fruit which is limited in time based on when the fruit is in bloom which means they can’t really be done all year around technically.
Answer: Really kiddush Levana could be done the whole month but the rabbi enacted that it should be done on the first half of the month therefore it is time bound. Whereas the happiness you get out of seeing a new fruit could only be had once the fruit is in bloom therefore it is not halachically time bound.