Find the weaknesses of the existing solutions and try to be better.
There is numerous examples of companies that did it. For example, Zoom was founded by the former VP of engineering from Webex because he saw issues in Webex.
Having competitors is a good signal as it means there is a market.
However, I would not go against a super huge player as they have a development team that'll likely "patch" the product and corrects the weaknesses.
Out of curiosity, what's your idea ?