I live in Norway, and for some time long ago Northern Norway not far Russian border. It's the reason I traveled first to Murmansk. These days in Oslo area. Russia is my main week-end and holidays place since many years, some 20 y. Included when on the way to Central Asia.
There were cheap flights Oslo-SPb, and fast trains Helsinki-SPb. I could finish work Friday early afternoon and be in SPb late evening, back for work Monday morning. I used to cross by air, by train, by minibus and with my car for longer holidays (ferries Sweden-Finland, Sweden-Estonia or road through Laponia).
So I crossed many times at many border points for years and years. After COVID travel restrictions were lifted, by end summer 2022, i traveled only four times, as the relations were severed by EU when military operation started in Donbass, and it took some time to adjust. But I still have not noticed people being taken aside for deeper control, excepted couple times, not in noticeable amounts or like a rule. Myself I had to wait a bit more once, just by the side of the control booth, for an officer to come, because the agent in post was unsure about my passport, that was at the time older non-biometric type, hence the hesitation of the agent. I just showed my national ID card, that confirms passport data, and he waived me a happy stay. But still no questions. Last crossing 17 June and same: no questions. Stamp on the passport, signing of migration card.
So, that's the reason of my surprise at you initial comment.
But then what I am thinking is you may be non-Schengen, "anglo-saxon" ie whatever kind of British spin-offs like Canada, USA, Australia, besides UK itself.
Because these countries, and I know from personal experience with Canada, have intrusive rules for pre-travel (to Canada, an electronic travel authorization),, intrusive rules at borders, and use the question/answer matching method (the agent asks a question that is part of the pre-travel authorization and expects the answer to match).
In case of USA, they even have infamous reputation for considering all foreigners wrong doers or terrorists unless proven contrary. My friends in Montréal, who use to holiday in Mexico or Caribbean, avoid like a plague transits through USA even if direct tickets from Montréal or Toronto are more expensive.
So, recalling this, I guess that Russian borders may have decided to play a similar game with "gringos".