Let me preface this by saying that I hate discussions about pay-to-win in MMOs, simply because I have yet to see any such discussion go anywhere interesting or useful. Since MMOs don't have a clear and indisputable win condition, whatever area you personally don't want to see people overtake you in is at risk of any related cash shop purchases being perceived as pay-to-win. I'll never forget Liore's post about how cash shops selling all those cosmetics kind of sucked the fun out of MMOs for her since collecting cool outfits had been an important part of her gameplay until then.
But even when we're talking about an aspect of the game that is clearly meant to be competitive and where most people would agree that they don't want money to buy someone an advantage, players are easily distracted by simple obfuscating tactics. People protesting about the Sword of a Thousand Truths being sold in the cash shop? Well, make it so that by collecting a thousand rare "sword shards" in game, people can acquire it without paying as well. Never mind that it's going to take three years and nobody is realistically going to do it, a lot of people will suddenly give it a pass if there's a way of getting the same thing without paying, never mind that it's not really viable in practice.
The only thing that I see all pay-to-win accusations having in common is that the cash shop items in question make people uncomfortable. To be fair, that also applies to things that don't necessarily have anything to do with pay-to-win, such as lockboxes, but let's use it as our standard anyway. Galactic Command boosters definitely make me uncomfortable.
To explain why, let me first talk a bit about what I tend call my secondary MMO: Neverwinter Online. There are definitely things I really love about that game or I wouldn't be playing it, but its cash shop is not one of them. I do want to give Cryptic money every now and then because it only seems fair when I've spent a significant number of hours playing their game... but deciding what I actually don't mind spending money on is always an agonising experience.
My biggest annoyance and the things I've sworn myself to never buy are what I would call anti-grind consumables. For example there is a process where you upgrade enchantments in your gear, but the higher you go up in level the higher the chance that the upgrade will fail and that you will simply lose all your expensive mats in the process, up to the point where the game will literally present you with a 99% failure rate. Except... you can avoid the issue by using a consumable from the cash shop! (Yes, they also exist as very, very rare drops that you can get without paying... but I refer you to my point above.)
Or take refinement, a related process through which you upgrade your gear in Neverwinter. For this you need to use up "refinement points", which again you do get through normal play, quite commonly in fact, but you need literally millions of them to actually fully upgrade an item, which is never going to happen for most people by playing normally - but once again, the cash shop offers relief in the form of expensive items that are worth tens of thousands of refinement points at once.
The reason these things bug me is that they are basically a sneaky way of trying to get a continuous stream of money out of players. I'm actually someone who is quite happy to continually support a game financially (aka pay a sub)... but be honest about it! Don't make your game free and then make it such a pain to progress that you have to shell out money over and over again (unless you're willing to literally just pay hundreds of dollars at once to get your items to cap right away).
What does all this have to do with SWTOR? Well, SWTOR does charge a subscription. But now we have a new, super grindy system for subscribers anyway, and lo and behold, there's also something you can spend money on to ease the pain for a little while, again and again. Not subtle, Bioware. The main mitigating factor in my eyes is that it's really a pretty weak boost. 25% extra CXP doesn't really speed you up significantly in the short term, and you still need to actually play too - the boost increases your Galactic Command gains but doesn't just "give" points to you. But it still feels like a pretty cheap move, and I think Bioware can do better than that. If Command XP were a thing for everyone and then subscribers got a boost to it automatically, fine. But paying to be able to grind and then paying again to lessen the grind is a poor way to be treated as a customer.
All that said, I will confess that I actually bought some of these boosts. Why? Because thanks to referrals, I'm sitting on tens of thousands of unused complimentary Cartel Coins that I never use for anything since I'm not really one to buy lots of cosmetics or crates of randomness. There's just little for me to spend them on right now, and at least these boosts are actually useful to me. I don't know how I'd feel if I actually had to pay for them with real money though. I don't think I would want to.