I know you are being lighthearted (🧐) but this isn't true.
I was in Tesco this morning as it happened. I'd a reasonable 'top-up shop' list. I specifically looked for items where there was a Clubcard reduction. I didn't buy anything we're the main non-Clubcard price was higher than other local supermarket prices.
My saving was €19.25 on a €75 shop.
Items included several 3 for 2 offers (available to Clubcard only), large bag of giant Buttons (love these - silly prices usually tho!) €2 (non-Clubcard price €3.25, €3.50 in Dunnes); Muller corner yogurts €3 (usual price €5, €5.30 or so in other supermarket).
And so on.
For balance, I didn't buy some items that were more expensive than my usual supermarket, including toothpaste, fabric conditioner, shaving foam.
It appears to me that all supermarkets are in the same position - some items will be more expensive, there's a range of 'offers', some genuine, some marketing trickery.
Tesco own brand is consistently really good, for store cupboard items, in particular & also for choice, and really affordable. Overall though, I still find the overall range not good enough in the Tesco closest to me.