I know the feeling well. I don’t attend the tournies over here in my Country as they are in different Counties and I can’t travel, so I’m restricted to ArcReq/Player Matches and Champ Mode.
Don’t take this as self-praise but it’s easy to notice on GFWL that 50-75% of the people you meet in those Modes are either learners (You know the type, not sure of moves, randomly doing punches and downfierces from mid-full screen testing out random Motion+Punch/Kick trying to get a move out etc), pattern players/mashers and a small percentage who abuse things. If I meet people of an equal level or that are clearly miles better than me via respectable means I like to add them to my Friends List - This ensures better fights or, if you don’t mind losing, LEARNING something from someone and knowing your opponent - You very rarely get anything out of random matches Online as people tend to win/lose a few then bugger off, or it’s too laggy, or they send lecherous hatemail etc
Before you even enter Random Matches or Arc Req, make sure there is nobody around that you’d prefer to fight (It should be a last resort to go to AReq etc) and if not then go into ArcReq knowing full well that the majority of fights may not be totally enjoyable.
Now, to the actual problem of ‘random shit’ by players - We all lose to it now and then. Sometimes people follow a pattern and while it may start to look like their ‘random’ garbage is getting the better of you, it’s up to you to learn that ‘pattern’ and BE PATIENT. Disect it, learn it, then dismantle it.
The most basic, BASIC example - A lot of Shoto’s I fight will religiously mash out SRK’s hoping to reversal my dropped combo’s or block strings. If they see it working, they often won’t stop. If you lose a round or a lot of health to the same thing, remember it, and bait it or just stop what you were being punished for and resort to safer moves if possible.
I’m a Balrog player - That means I have to be close to do damage and that also means that if I’m fighting above type of person, the largest chunk of my damage recieved will more often than not be because of mashed out random garbage or reversals. So, I take the time to learn if that is the type of person I’m fighting then go in again - If I enter a block string (expecting a Reversal, and they do it) it’s a free CMP>Super // Headbutt>Ultra or whatever I want. If I really want to drill it into people, I’ll throw them after every single whiffed SRK… Funny that when I do this, a lot of that type of person will… Wait for it… SRK on their wakeup as I walk up to their fallen character… Block, Throw, repeat.
Sad thing is, these people are often so strange that you cannot be sure if they’ll ‘learn’ not to do it - Thats the biggest problem. A pro player noticing something isn’t working will re-evaluate wether doing it again is worth it… The rest will likely just throw shit out anyways.
There is no real answer to your question because it can often boil down to the character you’re fighting or who you use, yourself. Most will have some kind of option to use repeatedly if the opponent is also doing something repeatedly - It all boils down to the fact that if someone is fighting with a pattern or random garbage, sometimes you can’t beat it with normal playstyle you’d use against a proper player thus you have to resort to battling garbage with garbage.
Example (Again, using mashing Shoto’s or reversal spammers) - As Balrog, using TAP to EX Headbutt is not something you’d really consider against a good player as they will casually block it and punish. Funny then that it is my 98% guarantee’d Ultra setup vs the above type of mashers because they see you ontop of them on knockdown “MUST MASH SRK WAIT WHY DID I GET HEADBUTTED OMG ULTRA WTF?”.
Another case I had recently was a Blanka player who did NOTHING but get up close and spam crossup jumps all day and sometimes throw in random Ultra for good measure making it hard to tell what was safe to do in response, or a Honda who does nothing but the flying buttslams over and over. It’s annoying as hell but if you don’t know how to combat it then you’re going to lose.
Stay patient, stay focussed and learn their shit (if it’s a pattern) and if it’s not, fall back, let them come to you and disect them. If you can’t hang back (like I can’t at times as Balrog vs projectile abuse) then get in their face but remain at a safe enough distance to punish any random unsafe bollocks they throw out.
Not the best of advice but do consider it.