Pro thinks we should be allowed to instigate as con, based solely on the fact that we are allowed to instigate as con. This is terrible logic, by the same logic we should be able to rape 13 year olds, if that is legal.
What pro fails to realize is that what should happen is far different from the reality of what does happen.
So the word "should" is really a statement on what is superior. Instigating as con or pro, or are they of equal value.
When instigating a debate you are making a statement about the belief system you wish to defend. If you are going to start off defending it, it seems silly to start with the con side. Look there is a reason why websites have pro and con lists and not con and pro lists, when we make a tough decision, we use pros and cons list not visa versa. It's dumb.
When you instigate as con, it implies that you aren't really looking to defend your belief but attack another person's belief. If you are pro choice it is easy to instigate a debate that says
"This house believes abortion should be legal" If you are pro life you should easily be able to instigate by saying "This house believes that abortion should be illegal".
There is also the subtle distinction between a positive statement and a negative one. Creating a debate and defending your belief should be done with a positive statement so you assume a fair amount of the burden of proof. For example if you believe aliens have never visited the Earth, by wording it so you are con you take the easy route and eschew any burden of proof and put it on your opponent.
Here is how a coward would word the debate "Aliens have visited the Earth" and then take the con position, putting a perceived extra burden of proof on the person accepting the debate. However if they were to word the debate "It is unlikely aliens have visited Earth" than they would be making a positive assertion and have a fair amount of the burden and they can begin making talking points such as how difficult light speed travel is, instead of taking the con possition and cowardly shooting down pros arguments and never making a case themselves.
In reality debates should mostly have both sides with some burden of proof, but given the fact judges are not sophisticated enough to know the appropriate burdens to place on debaters, than they can gain an extra advantage by instigating as con and merely shooting down arguments.
You can honestly see this cowardice with most instigated debates in one form or another, if the debater is not trying to game the system by taking a topic where they are arguing more of a truism like in every one of oromagi's debates than they game the system by instigating as con so they can be percieved as having a lower burden of proof by unsophisticated judges