Being in a condition that makes it ‘very difficult’ to knee can certainly be overlooked and not be excused as there isn’t anything you can do about the condition.
Why change any of the mass? Pope Pius X guaranteed it in it’s present form in perpetuity.
Which he had no authority to do, the form of the Mass not being a matter of "faith and morals", but of discipline.
None of the listed "bad things" had anything to do with my decision to become RC four years ago.
The problem is due to abysmal catechesis, and nothing else. (and yes, the RCIA program I went through was (and is) abysmal). Fortunately, I read the "Catechism of the CC" from cover to cover before setting foot in RCIA, so most of the claptrap simply bounced off.