In the beginning some people would label the keys with stickers and put ABCs on every note on the page. A few months ago came across an old piano on display. Many of the keys still have stickers on them. Matching letters of the alphabet doesn't require much effort... see an A, play an A.
A number of years ago I was at a gathering. 3 kids tried to decipher a piece with 4 lines their teacher assigned as appropriate for the level. For an hour they couldn't come up with anything that sounded like the song. If I was at a similar situation, I'd rather spend a few minutes to write letters on the page and put labels on the keys. Within an hour I would be able to play something (with some wrong notes) than trying to figure out most of the notes like hit & miss. Before we get good at reading, we still want to be able to play a few songs by taking the easy way out. Otherwise we'd quit early.
Think of each "note" on a page as a letter of the alphabet. You learn to recall each letter based on which line or space it is on the staff. Instead of thinking of letters of the alphabet as distinct symbols, you think of notes as looking similar except the circle is on a specific line or space.
People with perfect pitch can hear an A and know it's an A automatically. Other people who have the ability for relative pitch need to hear other reference notes before & after to determine what a note is. There are online links & apps to help you recognize notes by displaying & playing individual notes on the screen and you name the notes. Being able to recognize notes quickly would improve your reading ability.
When looking at the page, we're not just seeing random notes. We recognize beat patterns, note runs (up & down the scale), intervals & chords. The last piece I worked on was a tradition tune "House of the Rising Sun". Looking at the key signature with nothing I know the piece is in the key of C or A minor. The left hand notes A-C-E comes up I know I'm playing an A minor arpeggio. Before that I worked on an arrangement of Simon & Garfunkel "Sound of Silence". The song has a lot of repeated chord arpeggios like D-F-A (D minor) "Hello darkness my old friend" & C-E-G (C major) "I've come to talk to you again", F-A-C (F major) "Because a vision softly creeping".
The past 2 years my teacher made her students do a lot of scale & arpeggio exercises. They really help to recognize notes quickly.
The link to online note reading exercises:
https://www.musictheory.net/exercises