Well, let's make sure we're talking apples to apples. In that interest, I'm going to quote the entirety of the SPA below. Including it's current errata state, since the "proposed text" did not become erratum.
Antagonizer
Unit Type: Any
SPA Cost: 3 points
As combat talents go, the ability to enrage the enemy may seem
ill-conceived at first, but few can overstate how effective it is when
it draws fire from a wounded friend—or exposes the berserking
target’s weaker back armor at the worst possible moment.
Every enemy unit that comes within 6” of a unit using this SPA must roll 2D6. If the roll is 8 or less, the enemy unit becomes enraged. Enraged units must move as close as possible to the Antagonizer unit, taking the most direct, passable
and legal route toward the Antagonizer. The enraged unit ignores increased movement costs or possible damage inflicted by its path for determining the most direct path.
The enraged unit can only make attacks against its Antagonizer, unless the enraged unit has no attack that can target the Antagonizer. If the unit has multiple attacks, and only some of those attacks can target the Antagonizer, the enraged unit can make attacks against other targets only with those attacks that can’t target the Antagonizer. Attack from the enraged unit with an area of effect must include the Antagonizer in attack’s targeted area of effect.
If the enraged unit begins any phase more than 24” from or without line of sight to the Antagonizer, the unit is no longer enraged. This ability does not function at all versus aerospace units.
The red text is the errata v 1.1 overwriting the 2nd paragraph of what's printed in the ASC.
So a few points:
The clarification on how "coming within 6 inches" works basically means it doesn't only work during the movement made by the Antagonizer. It's obviously more powerful this way since not only can it be used actively, it can be used passively as area denial (come within 6" of this point, and you won't be allowed to shoot at anything but this guy). Being able to force your opponent to allocate shots, particularly highly damaging shots, on low-probability odds is very, very powerful. But what makes it truly powerful is that there's no cap on how many units can be simultaneously enraged.
Perhaps even worse than that is the movement requirements. At least the erratum doesn't let you force your enemy to walk thru minefields anymore. (or rather you CAN still do so, they just become immune to mines while enraged). Still, Alpha Strike is a game of maneuver and an ability to force your opponent to make uncoordinated moves (especially out into the open and out of any kind of cover) is imo the most powerful ability in the game.
However, TPTB did intend for some sanity checks to be in place. First of all, if the antagonizer hides and breaks LOS, then the enraged units are free to fire at whatever they want (if there's no LOS, the enraged unit has "no attacks that can target the Antagonizer"). Secondly, the Antagonizer may not dodge out to long range or else the same thing occurs. Yes it's very, very powerful to put on a high TMM unit, but at least the range can't be worse than medium for the enraged targets to be forced to shoot at it. In both of these cases, not only is the enraged unit free to shoot at whatever it wants, it's also released from the enraged "debuff".
So, yes. Putting Antagonizer on a unit with +4TMM is a no brainer of a decision. Honestly it really seems that's what's intended by design. Its a very powerful board control ability, perhaps the strongest there is. But in order to maximize its ease of use, you need to put it on a unit that will probably go away the first time the "crowd controlled" enemy units get a lucky to-hit roll. With a +4TMM, Cover, and Medium range, it's still a 12 to hit for basic skill pilots. It WILL eventually happen.
I kind of agree with the OP, but I suspect not to the same extent. I think Antagonizer would be fine as is, if it only could enrage one target at a time. It even makes sense to me in an in-universe kind of way. You really gotta focus on annoying someone to get them enraged and keep them enraged. Seems like it ought to be exponentially difficult, if possible at all, to enrage multiple targets into ignoring all tactics and common sense.