*facepalm* Do you people still not get it? Yes other characters can force tech, too. With Helena it's more persistent. It's a big strategy that makes her good since no matter what she has an advantage. Other characters force techs don't have the same luxury as she do. It's like how every characters has thows, but some characters has throws that makes them great like Jann Lee's dragon gunner.
And, bluntly, other characters can do it better. Bayman's not great at force techs but there's at least one specific 90+ damage unholdable set up for a force tech for him and most of the others will net him 50 or so from one guess and +20 advantage. Tina's got straight force tech setups as well as a juggle to pseudo force tech that guarantees either +6 or +22 depending. Zack looks like he's got some good options too.
I'm guessing the reason this may be so strong for Helena ends up being that she can always get a throw that will guarantee a combo starter (236f+p, BT f+p, BKO f+p) and since she can work the force tech game she can basically reset with a throw or get the force tech off any juggle. Arguably several characters can do something similar (Bayman/Tina have 44f+p, Mila/Bass/Hitomi/Zack have 6f+p), though Helena's options are actually guaranteed from BKO f+p and the BT f+p at least, aren't they? If this is her primary strategy I guess I'm ok with that, it's a niche she's going to have with the grapplers and Zack to some extent. I think it's a a viable design for some characters to have this and some characters to be unable to exploit it. The slower characters need this pressure while someone like Jann Lee is really only balanced if he does actually have to get off you once in a while after a knockdown.
However, I don't really know if Helena's version as she is will be viable long term. Bayman is sort of a special case as a "grappler" in that his throws aren't very good; his only real punishment option even against -10 is 4f+p or 44f+p and neither of those are very scary in terms of pure damage (44f+p should at least give him 3p from BT I think). If I had to guess I'd assume Rikuto didn't want to risk a hi counter throw into reset with an OH attempt and so he held back with those, and punishing with 44f+p isn't intuitive. There's a lot of characters that should still really be able to hurt Helena at -10 though (Hayate, Tina, and Bass spring to mind), so once people start to expect to need to input 236f+p or 44f+p from block Helena is in trouble. I think the matchup will tend towards the theory long-term more than this tournament did.
Edit: Watched the video. Non-story, here. Rikuto misses a couple techs and guesses badly in two matches, world grinds to halt, holy shit. As best I can tell there was maybe one actual force tech in the whole match from Helena (and possibly the 1kp that you can use as a guard break mixup). Everything else I saw I'm pretty certain is techable and shouldn't give Helena a lot of advantage. Any advantage is good against Bayman given his speed, sure, but you can see in the rounds where Rikuto got a pressure game going she got folded pretty quick. This is early game stuff here.