Most likely you can rectify this situation.
First, call the CRA's public number - might have to wait a while on hold - oh well! See their number here: 1-800-959-8281 https://www.canada.ca/en/revenue-agency/services/payments-cra/individual-payments/income-tax-instalments/claim-amounts-tax-return.html
Ask the agent when they see the payment on your account as having been received. Then ask whether the payment was initially applied to 2021. Most likely the payment was received, but wasn't originally applied to your 2021 tax year, perhaps just sitting in an 'unapplied' account. They are not likely to immediately resolve this for you on the phone, but they actually have the authority to do so, possibly. While you're on the phone, ask for help in setting up your CRA Myaccount - this will give you online access to your balance owed etc., and will be helpful for you in future years.
If they don't solve the problem for you over the phone, you will need to write a kind letter to the CRA requesting that they acknowledge the timing of your initial payment, and reduce their calculated penalty interest amount by the correct proportion. Include all relevant info in your letter, including attachments of bank transaction timing, etc., and a simple table showing the calculation of how you would personally calculate the interest amount. Again - be kind - you are basically asking someone to do a favour for you, saying that your intention was to make a payment to reflect on time, but that you were not expecting the total balance to be so high, etc. etc. etc.. An individual CRA agent has a fair amount of leeway, in terms of whether they would grant your request. You are basically asking for leniency because of your attempted 'good faith' effort to make the payment on time.
When deciding whether this is worth the effort, look at the actual amount that might change - [edited after re-reading your question] - since you are being dinged for the late filing penalty of 5% + 1% extra on each extra month of late payment, this process is highly likely to be worth it for you.
As a side note, I think you should reflect on whether you are putting your energy to solving this problem, or shouting into the void. The framing of your question is basically "Why is the system so unfair?" [which believe me, I sympathize with], when you could more pragmatically just ask "How can I solve my problem navigating the [terrible] system?" While filing taxes is aggravating, you are making things harder on yourself by not tackling it in the required timeframe. Be aware that you are likely to face deeper scrutiny and possibly penalty rates as well, if you fall into a similar situation next year.