Opera used to be a fantastic web browser, with a custom high-performance Presto rendering engine and features like tabbed windows that didn't show up in competing browsers until years later. However, the modern Opera browser is a shadow of its former self, reliant on chasing trends and meme advertis...
Since Hindenburg directly profits from the company's decline in stock, it's not an impartial source of information, but the company's other reports into companies like Nikola have held up to scrutiny.
I wouldn't consider them that terribly biased personally; as their livelihood (Money) is put into shorting whatever company is being reported on (Mouth). Literally they put their money where their mouth is...and if they make a horrible mistake in reading a company going under and doing really shady things; they're going to basically go out themselves pretty quickly and lose a lot of credibility in the process.
Is it maybe a little scummy? Yes. But as they're calling out scumbags anyways; it looks more like a legitimate application of "taking a scammer to know a scammer". It's better that they're legitimately profiting from calling out companies that are cheating everyone and reporting on it to benefit the public in the process.
Yeah, Hindenburg isn’t like a team of journalists or anything, but if they cited other sources in their report and it seems to be pretty accurate. If there were big issues then Opera should have been able to point them out, and that didn’t happen.