It's not a question of "price" costs. Its about "opportunity" costs. Using resources and manpower on building a huge submarine fleet means that you can't use those resources for purposes that improve your peoples lives. An aircraft carrier doesn't generate economic returns, while a new train line does.
A huge submarine fleet would be worse than an aircraft carrier in terms of wasted resources... it is a bit like having 40,000 tanks and all the necessary supporting vehicles when there is no interest in invading europe... it makes rather more sense to have maybe 6,000 tanks that can be moved rapidly to where they were needed plus having enough IRBMs to obliterate any armoured threat coming from Europe or elsewhere.
Having no tanks makes you vulnerable... an eggshell... either all or nothing, so you need some conventional might.
It is the same at sea, you need to be able to operate anywhere in the world... and if you want to operate away from mainland Russia or allied countries you need an aircraft carrier to support your operations.
It doesn't need to be a US designed 100K ton super carrier... if they can make that multihull 45K ton carrier with slightly better aircraft capacity than the Kuznetsov then that would be perfect... as long as they can put a decent AWACS platform on it and modern capable fighters... ie Su-57 rather than Yak-41.
USSR didn't tank because they were investing in nuclear deterrent (it was one thing they were mostly smart about) they tanked because they were wasting money and resources on overbloathed and redundant conventional military
They already had nukes but they still wasted money on huge pointless conventional force that they would never get to use because whole thing would have gone nuclear anyway
They should have just put nuclear component on 24/7 hair trigger alert, make sure other side knows the score, disband everything but basic conventional units and redirect the money into economy
But they didn't do that because they had idiotic irrational fear of nuclear war while Americans were never afraid to press the red button on moment's notice, better dead than red and it paid off big time
Instead of accepting reality and focusing on welfare of their people they were just coward pussies who thought that some tanks would stop the inevitable
Interesting that you think they went full cycle... from Stalin saying Russia was backwards and will be crushed by the west if they don't upgrade, to out producing the west in conventional military means and destroying themselves...
The real question is... at rather more than a trillion dollars a year in "defence" with US demands for more spending by their allies, is NATO headed the same way?
Right now 4% of GDP is the gravy... it is the extra money you can spend on healthcare and education and parks and people to make life better and more comfortable for everyone...
When balancing a budget you pay the critical things first and luxury items last but it seems the military spending is doing away with the luxury items and the saving which is both uncomfortable and short sighted.
Nuclear submarines are part of naval component that keeps you safe not some overpriced bathtubs that do nothing of relevance and are just sending message that you don't plan on pulling the trigger when it matters
Bullshit.
The only subs that really matter are SSBNs and with the numbers of missiles they carry and the number of warheads on each missile they need less than a dozen to do the job... everything else is bullshit... they could simply block off the ports with nets and mines or sail their SSBNs up rivers and do the same and just launch... once the missiles are launched which would take less than ten minutes they have no further value.
How is an SSN supposed to save an SSBN from being attacked?
Jump in the path of a torpedo like some bullshit hollywood movie?