Most of the arguments that abound stating that the skill summon golem is overpowered are based around a couple of things.
One: Golems out damage high-end melee players. Wither this is single hit or dps is generally not really spelled out in these arguments, they just state this flatly.
Lets try to understand this point. When they refer to high-end melee players, they are very likely referring to the melee player's wm skill vs golem's wm skill and smash vs smash, as the apparently accepted melee tactic is smashmill, and nothing else.
Melee characters have more melee options than golem. Golem has wm, smash, stomp, and defense. Stomp is a support tool when used by a golem at best, if used at all and can generally be ignored. As far as I know most giants only rank it for the STR anyway, pvp lulz, or for use against red dragon.
Defense is largely useless on a golem as well. Therefor golems only really have to relevant skills: smash and wm. While smashmill is a decent strategy, melee players have access to skills like assault slash, charge, final hit, and counter attack. Melee players can also use bolt spells to do tactics like ice tennis, bolt counter, and so on.
You also can't control pets while controlling golem.
For actual melee combat, the golem only has size and damage going for it, but it is by no means a complete substitute for a real player. It is highly limited in melee options, and cannot make use of any of the hybrid options available to a real player.
Damage is important, but there is more to playing melee than just damage. Using the tactics available to a player that a giant cannot do, a player can outperform a golem. If you limit yourself, as a player, to only smashmill, then you are a bad player. I see nothing overpowered about a golem doing better than a bad player.
Two: golem somehow renders melee players obsolete: What is the basis for this statement? Fireball makes melee obsolete, is it overpowered? Fireball, especially when used in a group of people, is far more devastating than a melee player. In situations where there are large numbers of targets, fireball does greater single hit and greater dps than a high-end melee player.
Fireball is also much cheaper cost wise, and far easier training wise to get to rk1 than building up a complete melee player's gear and skills. Heck, it is easier than golem. It will be even cheaper to use/maintain than golem come g14 with personal farms.
Clearly fireball is overpowered, because it makes high end melee players obsolete. Why does golem get special attention for being one of the many skills that do this?
Three: High-end melee players deserve equal standing to other classes. They should be able to complete evenly with other classes.
Just because you can design a build or class doesn't mean it deserves to be as good as everything else. Some builds are simply better than others. Sometimes this is by a very large amount. Mabinogi doesn't have classes. There is -nothing- stopping you from getting whatever skill you want and using it for your character.
Before someone brings up the destiny system: You can choose the knight destiny and still summon a golem or equip a fire wand and cast fireball. There is no -class- system in mabi that limits you to using pure melee.
Everyone will end up the same: if golem is such a good skill, then yes everyone should get it. Just like people having been saying for years that everyone should get WM. You can play a perfectly effective character without WM, just like you can play a perfectly effective character without golem. Many players don't bother with the most ideal selection of skills, otherwise we would all end up elven ranger/mage/alchemist hybrids spamming crash shot.
As for why KR players are all QQing so hard, who knows. Realistically they should all be spamming fireball, not golem.
Newbies getting powerful fast: As much as this might chafe your chaps, this is a good thing. If you're the sort of person who hates the idea of other people having an easier time playing the game than you had, gtfo. This happens to -all- mmo's. If you create a game and the community stagnates, people get bored and leave. The only way to keep the community fresh it to bring in new players. And for those new players to enjoy the game, they have to have it easier and faster than the veterans had it. If it takes them the same three years to develop their character that it took you, then 3 more years worth of content will come out before they can do the same activities you do. By then you will be doing something else, and will have a 6-yr old character. They will never catch up.
If you want to enjoy a solo game, go play an offline console game like Elder Scrolls series of games. You will never have to worry about some newbie coming around and getting to near your level of proness in a shorter time than it took you.
In summary, people are whining about golem being overpowered because they are ignorant and don't understand game balance. Concerns like cost vs reward, veterans vs newbies, and build A vs build B are all meaningless.