Whykido

 Why try to functionalize Aikido instead of do a more "practical" martial art (the most common suggestion being BJJ and/or kumite point fighting)? Because your alternative you have suggested isn't going to get the Aikidoka what they are striving for. There are two issues here: first is technique, and second is ideology.

There are three ranges of Aikido technique. 

1. First there is stand-up grappling, what they would call "clinch" in MMA or Muay Thai. In the case of Aikido it is paramount that they stay on their feet, because it is a self defense oriented system (rather than a pit fighting system) so that they must take the possibility of multiple attackers - who may not yet even be identified - seriously. The only traditional unarmed Budo with this exact objective is Sumo, and Sumo influence on Aikido is no coincidence. This type of grappling is common in other internal martial arts in the form of Push Hands and San Shou.
2. Second there is knife-range techniques. These include both disarm techniques AND attacking techniques. On one hand being attacked with a knife is one of the most important self defense scenarios to train for, while on the other hand pulling a knife is one of the most practical ways to fight off multiple attackers.
3. Third there is a walking stick self defense system deeply encoded into Aikido, for the obvious reason that a walking stick is one of the most practical non-lethal ways to defend yourself known to humanity.

More practical martial arts might teach the physical skills needed to do type 1 technique, but only Muay Thai, Sumo and Push Hands fighting actually tries to implement it - so the BJJ, Kumite Point Fighting or whatever else you have probably suggested most likely will not suffice. Sure everyone needs to cross train in grappling if for no other reason than to learn how to escape from the ground, but the only systems that even score grappling escapes are Collegiate Wrestling and Combat Glima, and ground escapes just so happen to be beyond the scope of what most Aikidoka are training for:

And virtually no other martial arts are concerned about ranges 2 and 3 while encouraging free sparring with this kind of technique. A lack of free sparring is the whole problem with Aikido in the first place, so adding your non-sparring dogwater won't do them any good. Alternatives-to-Aikido generally do not combine all three ranges of Aikido technique together in one place as Aikido does.

Beyond technique, Aikido has a specific pacifist-lite ideology of trying to bring humanity together in peace and harmony - and even has it's on form of spirituality as it is rife with supernatural theories on Qi. Like BJJ or almost any other belt-ranked martial art, if the practitioner does not have some other religious system they use to morally reflect and improve their behavior, Aikido often fills that void. Asking an Aikidoka to instead become a Judoka isn't ideologically any more practical than asking a Christian to become a Muslim, and it will likewise have a low frequency of success.

While I have incorporated a small fraction of the Aikido I learned into my training, I have no intention of studying more Aikido. However if you want to understand why people are trying to functionalize Aikido, it is because Aikido's ideals represented in both range of technique and ideology are both worthy - and with further training through free sparring - practical: