EasyJet Baggage Fee Dispute - I Demand Refund

On June 16th, while waiting for the gate number announcement for my flight from Dalaman at 15:35 (the gate was meant to close at 15:55), the plane's delay became obvious. We waited for 2.5 hours without receiving an explanation. The departure time was listed as 18:55. An hour later, all passengers heard the 'final call' message on the screen (before EasyJet had issued the gate number). Everyone ran to gate 7 to get on the plane. After our boarding cards and passports were examined, an EasyJet staffer informed me that my two cabin bags were too large, despite the fact that their measurements matched those listed on the EasyJet website. She forcefully insisted that I read all of the terms and conditions to comprehend the flight circumstances, and she explained that the sizes were wrong. She informed us that we had to pay £39.99 per cabin bag or we would be unable to board the plane. She confiscated our passports and was really disrespectful, threatening to summon security to inspect our stuff. She eventually permitted us to pay for only one suitcase (I received a hazy payment receipt with no specifics), and it was almost too late to board when the bag was transferred to the plane's cargo hold. Why subject travelers to such torment? Delays, followed by an irrational penalty. It was a dreadful experience; I've gone to numerous countries with the same cabin bag without incident. The overhead passenger space above our seats was unoccupied, there was space available, and my huge luggage was already in the plane's cargo, so I had to pay to transfer my bag to cargo for no apparent reason. This experience has already revealed enough about EasyJet's services; how can I trust offers if the price rises? I demand a reimbursement for this circumstance because I do not believe the treatment we received was reasonable or fair.