[Knuckle]

I had a TLDR paragraph. Going to consolidate it. Basically I think you have two ends of the spectrum: Necromancer and Druid, as far as "easy solo" goes. There are other solo classes in between this spectrum, but I believe these two embody the definition of "easy solo" due to the options available to them.

Easy - Micro based - Specific Combat Encounters (what is the easiest way to kill mobs alone only, no other context)
For this definition of easy, I believe the necromancer is the clear answer for the below reasons:
1.) Feign Death is the best get out of jail free card in the game in my opinion, even though the spell version has cast time. Anytime you can reset a mistake, that makes an encounter easier to learn from as you avoid the frustration of a death and corpse run.

2.) Summoned Pet: Necromancer Pet's are pretty darn good, and not only act as a great dps/minor tank, but also allow the necromancer to have yet another escape tool to channel a gate, cast feign death uninterrupted, or simply run away and buy a few seconds.

3.) Lifetaps/DoTs/Fear are great ways to kill mobs, the bone knight is a great example of how an INT cast can facetank to 50 with only minor effort required thanks to a lifetap proc.

4.) Access later on to IVU/Invisibility for extra travel safety.

5.) Fearkiting outdoors is insanely simple and safe for necromancers to kill mobs.

For those reasons, I award the Necromancer the easiest solo class for in-combat encounters with no other consideration.

Easy- Macro: Overall Everquest experience leveling solo, including traveltime, vendor accesibility, income generation, and of course ability to slay monsters alone effectively, singularly or in groups of mobs.

Druid is the champion here, because they have so much time saving convenience built in a necromancer can not begin to compete:

1.) In high population hours, starting at level 19, the druid can access multiple locations freely at no cost to themselves, almost always ensuring a location can be found to effectively solo monsters, this can also allow druids to have a better shot at "rare camps" where highly sought after items are farmed. Non teleport classes must commit to parking their ass nearby hoping for a shot at the camp, while a druid can freely teleport around the world until it is closer to their chance at a camp they are in line for(disputable to some, and not applicable to "list" camps).

2.) SoW decreases travel time further, and has 100% uptime on druid. Provides additional plat tips here and there. Allows easy escape in majority of scenarios, excluding some dungeon situations and some spellcasting NPC scenarios.

3.) Root/Rot or Root/Nuke is the simplest solo strat for braindead grinding. Excluding undead, necromancers do not have access to this faceroll strat for soloing mobs. Not always mana efficient, but EXTREMELY simple, this is the easiest way to solo mobs. As a afk WFH player, i killed many mobs this way due to low actions per minute required, could easily med to full between respawns.

4.) Versatility - Versatility doesn't equal easy, but the fact that a druid can snare kite, root/rot, nuke/root, charm kite, charm tank, and eventually quad kite give them an answer for most encounters, and pretty much all outdoor solo scenarios.

5.) Druids are all good races = far more access to vendors/selling/spell upgrades than the necromancer class which can be killed on sight far more often for the newbie soloer.

Reason Shaman/Mage/Wizard/ENchanter are not listed:

Shaman - No teleport, more situational in dungeons than necromancer with no FD.
Mage - No convenience, higher risk of death without picking specific fights, no crowd control except pet.
Enchanter - No convenience except for faster mana regen, higher risk of death than necromancer/druid for newbies.
Wizard - This would actually be my third choice right behind necromancer and druid believe it or not. They function in a very straightforward way and have the utility of teleports which in my opinion does increase the "easy" factor on the convenience scale way more than any non teleport class. In a combat encounter you root/nuke and that's it. You can clear camps with guaranteed roots by bursting and camping out, mages may not be able to get away with this due to root pet dependency or it staying alive long enough to camp out after killing a mob(when clearing larger mob aggro groups).
Wizard would basically be option 3 as far as balance between convenience and ease of combat, but they have too many limitations to beat out the druid, and not as combat effective in as many scenarios as the necro + less survivability than either.

Honorable mentions: SK/Pally/Ranger/Cleric.

Hybrids are more gear dependent which by its nature alters the argument of easy, assuming a "natural" leveling experience where you arent given a major twink advantage, I can't place them above the other classes. Cleric's can be effective soloers against undead mobs, but that heavily limits where you can solo effectively and also lack the conveniences of fast travel or feign death.