As far as the first part of your question is concerned, I believe you wont be able to secure a seat at ICE at NSIT Delhi, under Outside Delhi Quota, being from General Category with 97.04 Percentile.

For more information about JAC Delhi Cutoff List for DTU, NSUT and IIIT Delhi do follow the link below

https://engineering.careers360.com/articles/jac-delhi-merit-list

You have fair chances of securing a seat at NITs, IIITs as well as Good GFTIs with 97.04 Percentile.            For more information and college prediction on basis of JEE Main Score do follow the link below

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

For the Second Part of your Answer, I believe this year the cutoffs maybe higher for a particular Branch/Course when compared to 2020 or 2019. Firstly youve 4 JEE Main Attempts, and students competing for the Top 20k JEE Main Ranks, mostly keep improving through the attempts, rising the competition. Secondly with this Gap you recently got due Covid, between the first 2 and last 2 Attempts of JEE Main this Year, its more like an opportunity and many new students will get added to the race for Top 20-30k JEE Main Ranks, who perhaps used to target above 50k Range. Hence, surge in cutoffs for universities and institutes admitting through JEE Main.