There is a lot of concern about giving the vaccine to young kids because this is still considered experimental and nowhere near enough long term testing has been done.
While the manufacturers are immune to lawsuits due to deals made with governments, the fallout of a unforeseen long term health implication would still cripple them. Part of the issue is that for Public health you accept the health impacts on a few to save many. However in this day and age, those few have a much larger voice and impact. If you or one of your family is in that small percentage the rest of your life will suck badly. if you have FB you can check this link of people with adverse reactions to the vaccines
No More Silence
Just for clarity's sake, the limited legal immunity you mention is provided by a Declaration under the Public Readiness and Emergency Preparedness (PREP) Act. The Declaration was made 4 Feb 2020 by HHS Secretary Azar.
Despite this immunity, there is relief for those who are severely affected, through the Countermeasures Injury Compensation Program, although I have read that compensation is awarded extremely rarely.
Details here:
https://www.govinfo.gov/content/pkg/FR-2020-03-17/pdf/2020-05484.pdf
"The Public Readiness and Emergency Preparedness Act (PREP Act) authorizes the Secretary of Health and Human Services (the Secretary) to issue a Declaration to provide liability immunity to certain individuals and entities (Covered Persons) against any claim of loss caused by, arising out of, relating to, or resulting from the manufacture, distribution, administration, or use of medical countermeasures (Covered Countermeasures), except for claims involving ‘‘willful misconduct’’ as defined in the PREP Act."
"Before issuing a Declaration under the PREP Act, the Secretary is required to determine that a disease or other health condition or threat to health constitutes a public health emergency or that there is a credible risk that the disease, condition, or threat may constitute such an emergency."
"In deciding whether and under what circumstances to issue a Declaration with respect to a Covered Countermeasure, the Secretary must consider the desirability of encouraging the design, development, clinical testing or investigation, manufacture, labeling, distribution, formulation, packaging, marketing, promotion, sale, purchase, donation, dispensing, prescribing, administration, licensing, and use of the countermeasure."
"The PREP Act authorizes the Countermeasures Injury Compensation Program (CICP) to provide benefits to certain individuals or estates of individuals who sustain a covered serious physical injury as the direct result of the administration or use of the Covered Countermeasures, and benefits to certain survivors of individuals who die as a direct result of the administration or use of the Covered Countermeasures. The causal connection between the countermeasure and the serious physical injury must be supported by compelling, reliable, valid, medical and scientific evidence in order for the individual to be considered for compensation."
Obviously, the above relates to the US situation. If I can find Canadian info, I'll post it.