Lets talk about Voltaxic Rift.

Voltaxic Rift is a lightning-damage bow that back in the beginning had two very significant modifiers: "100% Lightning Damage converted to Chaos Damage" and "Your Chaos damage can Shock".

Total conversion of damage to Chaos was easier to achieve back then, and much more tolerated because Poison was radically different. Back then, it was "Deal 10% of hit's poison-capable damage as Chaos Damage per second, for 2 second. Maximum 1 Poison stack". It was also extremely difficult to get - Viper Strike dealt chaos Debuff, Caustic Arrow (or rather, Poison Arrow) was mostly used for levelling and, ultimately, there were very few ways to make your attacks or spell be able to poison. When you heard "spell poison", mostly it was about a Fire mage with Consuming Dark + Infernal Mantle, a combination that gave 100% Fire2chaos and made Chaos damage poison.
There also was double dipping: if you boosted your chaos damage, you would boost both the attack/spell damage AND the damage from the poison it could inflict. There weren't all the mumbo-jumbo DoT mechanics of nowadays because, well, we achieved more with less. They were easier time, with easier solutions.

Then 2.0 happened. GGG has a penchant of taking a Mechanic and revamp it at every league. With Perandus and the new Labyrinth (yeah, we did not have ascendancies back then), that mechanic was Poison. GGG introduced new Physical spells (like Bladefall) and wanted people to play with them - so they took Poison and made it the DoT you know now. Numbers were stronger (Fatal Toxins back then gave 100% Increased Poison Damage, not the actual 30%), so pretty much every Shadow and Ranger who wanted to become the new Emperor would have sank a poison-dripped blade on Izaro's undead throat.

That said, very little was done back then with the ele2chaos conversion. And that's exactly where Spark abuse came in.

For you see, back then there also was no limit on maximum projectile travelling distance (now is 150 Units). So, it was indeed extremely easier for a Scion take a Voltaxic Rift, build up a lot of projSpeed, equip with a Drillneck (back then Pierce was something calculated in %, not in numbers, so having 100% Chance to Pierce meant every projectile could pierce... and Drillneck would have given an extra 100% Increased ProjDamage "for free") enter a map, cast some full-chaos Sparks and literally full clear it provided it was an outdoor with no arenas (which was mostly the case) from dozens of screen of distance. Sure, damage to one single enemy far far away would have been little, but the extra power from Poison, the easiness you had to build up a lot of poison by just allocating a couple of Notables AND the fact double-dipping was a thing made it extremely easy to full clear maps with little to no risk. Just build up as much Chaos Damage on your passive you can.

After allowing the playerbase some fun in Perandus, GGG made Prophecy and searched for a compromise. Many ele2Chaos was nerfed in a non-legacy way (there are still some legacy Consuming Darkness, but they too had their value lowered), but the nerf came with the new toys - ED/Contagion. Spark/Spork (spark + fork) build found themselves with three broken kneecaps - most to their stupor of having a third leg. Voltaxic went down to 60%, Travelling Distance became a thing and Ascendants were changed. These combined are the lid of the Coffin of the Voltaxic Spork Builds back then.