Electrolyze is a fairly good card, but what if it costed:
? Would it still be playable?
? Would it be broken?
? Would it be used in mono blue?
? Would it be used in every deck?

Just wondering.

In order:
-Not really.
-Yes.
-Of course it would it if it weren't banned. Also it would be a major break of the color pie as that is not what Hybrid is for.
-No because it would certainly be banned across all formats and casual players would hate it too.

In Order:
#1 - Would still be used in every blue/red deck in Limited, but wouldn't see a lot of Constructed use.
#2 - Maybe not in Legacy, but certainly everywhere else.
#3 - Yes, of course it would. 1 mana for 2 damage and a card? Huge upgrade over Shock, even an upgrade (can target multiple targets) over the cycling effect of Deem Worthy for (insanely) lower cost.
#4 - Yes. Every deck. Maximum amount. Why wouldn't you?

#4, Deck thinning is nice, but if you've got your deck pretty well set out to deal with everything you might not?

That doesn't really follow. It'd be like asking you "Would you like to play with a 56 card deck?" and you saying "No thanks. My deck's pretty well set out to deal with everything.". You should be saying "heck ya!" and tossing out a few cards to better improve your odds of drawing the right cards.

Also those four "free" cards are Shock+ and "draw a card" as the same time. There is no reason at all to ever not run four in any deck ever.

But what if you accidentally draw your last card? Just kidding.

at you would run 4 in every deck even if that took you to 64 cards because it replaces itself and has a positive effect. Street Wraith wasn't the universal include people thought it would be, because the deck thinning isn't worth the life most of the time (My sole disagreement with Yarium: a 56-card deck isn't *that* good on its own). When you are doing something for nothing at no opportunity cost? You have no excuse. Gitaxian Probe is already heavily played as a 0-mana cantrip (unlike Wraith it can do its cantrip thing on a random spare instead of life, and it has a positive effect)

Probe isn't heavily played anymore (in Modern, where it was a staple for years). Banning will do that.

A lot of speculation Wraith may join it next week. Now the 4th most frequently played creature in Modern.

And let's not get into the absurd prices Mishra's Bauble have reached.

There is a slight cost to zero-mana card draw: loss of information. Getting them in your starting hand makes your mulligan decisions harder, since you don't know what cards will replace them. You can also have that uncertainty during the game if you don't immediately cast them as you draw them.

(The benefits can still easily outweigh this cost, especially for this hypothetical where you get a significant effect added on. I'm just saying the cost isn't completely nonexistent.)

That uncertainty is completely negated by the card also being a free good burn spell.

i like the idea of a zero mana cantrip because it causes one to question what strength is

to simplify the case even further:

Ghostly Cantrip -
Instant
At the beginning of the game before you draw any cards, if ~ is in your deck you may reveal it and exile it.
Do Nothing

So this effectively just lets you run an actual 56 card deck, and every deck in magic benefits from using it, but none are improved that much for it. The card is run in every single deck, but might result in an increase of winrate that is significantly less than a card that is only run in some decks (even within a certain archetype).

Why make the card if every deck would run it other than to drive sales in a horrible way? Making 56 the deck limit is far easier on production.

the point is to question the meaning of card strength and not to justify bad cards

Storm Crow is a meme.