Did you even play the original?
Cause Shines 100% blows up reactor 5 as well as the pillar that supports sector 7.
The first explosion is hinted at being caused by Shinra as well by the very same scene you mentioned...
LOL, you're not really serious about that, are you? I could return that same question.
For reference, here's Barret's exact words when they first meet president Shinra in reactor 5:
Barret: Don't give a damn 'bout none of that! This place's goin' up with a big BANG soon! Serves y'all right!
Avalanche DID place a bomb in reactor 5, in case you've forgotten. Just the timer wasn't visible this time for gameplay reasons (there was still a cutscene and a boss battle coming up, so they probably didn't want to pressure the players too much), but the original game never left any doubt that this was Avalanche's bomb.
And on a side note, it wouldn't make any sense for Shinra to blow up the reactors themselves. They are ruthless, yes, but like any company their prime objective is earning money, and as an electric power company the reactors are their main source of income. If they wanted to denounce Avalanche as evil-doers, they could've easily done so in other ways. From a business point of view, demolishing your own production is devoid of all logic. (And I'm actually surprised that Nomura, who is also among the leadership of a big company, seemingly doesn't understand that.)
And Jesse wondering about her bomb's strength isn't really a "hint" for any sort of conspiracy from Shinra. It's far more likely that she just made a mistake when constructing her bomb. Everybody makes mistakes from time to time, that's normal, and Jesse even made another one with Clouds ID card on the train, so we already know her work isn't always the most reliable.
Oh, and to answer your initial question, I've played the original more times than I can count over the past 22 years.