Yes, these are natural concerns. This is - more specifically - how it works:

Twitter - like other websites - responds to numerous reports of abuse daily.

Some of thse reports are in the form of legal "cease and desist" requests.

If Twitter does not remove the abusive post or suspend the abusive account, one can hire an attorney to request further action (on any number of a broad range of alleged abuses).

Moreover, Twitter's board and administration determine what they wish to prohibit at the website, per their policies.

Users are warned when they violate the policies, at which time, or soon thereafter, they are potentially suspended.

If someone wants to sue Twitter because of an abusive user, it will be necessary to try the options above first, after which a lawsuit can potentially arrange a cease and desist order against the content or user, but this is rarely necessary.

In the case of Trump's Twitter suspension for 2 years, this was due to inciting violence.

As for Wolf, she's guildy of disinformation spam and of working as a professional "influencer" who is spreading that disinformation, especially when that disinformation can cause grievous bodily harm (GBH) and in some cases, death. Twitter has a policy (as to other websites) that forbids this, the consequence for which is a suspension.