You're not alone with your struggling against blue, but then again I'm probably just one of the many 'mid-tiers' who have bad timing so what do i know, maybe the 15 year players will bestow some of their unreachable dueling knowledge upon us!!!
or you know, blue's interrupts are actually a problem and the masses of people that complain about it aren't bad at the game, as a certain someone is trying to suggest
There are a few approaches to balancing fast styles vs slow styles and dealing with the interrupt stuff.
Some people advocate for slowing down the styles, remaking their animations, making certain swings cause spinning attacks and so on, generally impacting the feeling of using fast styles negatively in some way or other. Although I disapprove of this for blue style, I am still of the opinion that cyan would do better as a medium style.
The other way to balance fast styles vs heavy styles is to focus on their strong point and tune down other factors. For fast styles that would be their swingspeed and for heavy styles it would be their swing damage. The focus should be on these things.
However, things immediately become far more problematic when you have ACM to worry about. Further exacerbating this is the fact that blue and red for example, don't have very different AP/BP like in the past. As I explained before, it is the fast swings + ACM reliant meta that causes such problems, because it means you are forced to attack back all the time or fall behind and be slowly ground down by a building ACM avalanche. The popular dunning-kruger solution to this is to want to normalize everything, slow swings down and add spins etc, which basically just ruins blue style and makes everything feel the same. Oh but we have perks. 10% more parry damage or whatever, is somehow going to fix things. Yes yes.
The dynamic to deal with blue should be simple to understand. Avoid getting interrupted by blue swings, defend and wait for a gap then press back with a swingblock combo. Use footwork to make it more difficult for blue to attack you (at range blue is weaker).
^ This should be how blue is dealt with, it should be the core of blue vs other style (yellow) gameplay. But when you add in ACM + perks, things become way more difficult to handle and balance and I hope I don't have to lay it out to you why that is.
As another example, let us take red style. Imagine a big, heavy hitter with low BP (weak defense but high offense). Now the dynamic changes again. You shouldn't be able to fight all styles the same way and win! Now, It's suddenly about dodging/PBing/parrying those big meaty swings and weaving in and out between them as you try to hit red in the bounce anim to drain alot of BP. The frequency of attacks is lower, but each attack matters more. All of this is erased, blurred and almost done away with if you introduce public-style ACM and tweak the AP/BP values to be near each other which is what happened. Thus you end up with a system where all the styles are kind of the same thing, just with different swingspeeds and perks and people fight blue the same way they fight yellow and wonder why blue is so strong and why they are getting raped.
---
Finally the thing about interrupts. Being forced to play a short block anim every time you are hit/interrupted and so on, is the problem in this case. Not fast swings vs slow swings. This issue is easily dealt with by reducing the frequency of block anims being played and defining when they are played. You should still be punished for noobishly starting a swing up close and getting hit in your start-up anim as 'mid-tiers' (noel) are wont to do. I don't think it should be perma-lockdown to fight against a blue user in close range, but that problem stems from block anims being played too frequently in wrong scenarios. Something that I think should be fixed, and will be fixed.